Thunder Cats 2011 gets growls (pun intended) from the older fanbase due to the art style, storyline, and character plot changes, all of which were accused of being too 'generic anime-like'. For example: Snarf was accused of turning into a cliche cute pet sidekick that doesn't speak and is just there to be the team's mascot (never mind that the original Snarf wasn't very well-liked), Tygra was accused of being turned into Lion-O's rival/borderline frienemy who just so happens to be interested in the same girl but will come through for him when it 'counts' to show that he 'cares', Lion-O himself was accused of having been turned into the late teen/young brash man that has to 'learn' to believe in himself and his power... Then there's the 'love triangle' between Lion-O, Tygra, and Cheetra which did't help quell said 'anime' notion... and this was all before the show even AIRED!
Cartoon Network. So many people, especially teens who grew up with the channel. Fans tend to have different ideas of when and where the channel went wrong. Popular ideas include:
Ending of the original Cartoon Cartoons.
Introduction of live action shows. Justifiable, though. It IS Cartoon Network.
Importing Canadian shows like Total Drama, Sixteen, and Stoked. Total Drama gets various levels of crap, ranging from low amounts from people who thought it was one of the shows that wasn't terrible to high from viewers who didn't get the point and Moral Guardians. And Owen haters...
Sixteen is another example. Some people hate it, some people love that it has a somewhat more realistic plotline.
Many Cartoon Cartoons are available on the sister channel Boomerang, but it's not exactly great with availability.
The Noods (the white characters that got splashed with paint to form a character), especially by fans of the older bumpers.
The announcement that a reboot of The Powerpuff Girls slated for 2016 would NOT feature the original Blossom, Bubbles, and Buttercup. Though they have voiced their support for the new talent, they are regrettably disappointed because Cartoon Network supposedly never called them.
Any of the RoboCop cartoons will do. Hell, the second one gets more flak because Murphy simply has more gadgets, and he gets called "go go gadget cop". That nickname might have less to do with just the gadgets and more to do with one of the most commonly used gadgets was extendo-arms, and that the series liked to find excuses to turn him into an incompetent recipient of goofy slapstick.
Transformers: The phrase "TRUKK NOT MUNKY" gets used every time a new series comes out. The Transformers fandom is the trope namer for Ruined FOREVER with good reason.
We'll never know how the fans' heads exploded when they first saw the character designs for Transformers Animated, or when they found out it would have human villains, with the Decepticons being a recurring threat and not the only one, or the fact that Optimus Prime would be voiced by David Kaye (who before has primarily voiced Beast Wars' Megatron), or that Optimus was a firetruck (until they realized he was technically a semi-truck outfitted as a firetruck. Then some were upset that he didn't have smoke stacks...), and let's not forget about Optimus not being the leader of all the Autobots. People even went berserk over Soundwave not sounding exactly like the old one (Frank Welker is expensive nowadays, one presumes). Transformers Animated, however, managed to convert many of those same naysayers through much story, design, and casting Shout Outs that show that the writers had indeed Shown Their Work. Even so, some Fan Dumb just won't quit.
Transformers Prime gets a lot of flak from fans who agonize over how the design aesthetic, particularly for the Decepticons, strays too far from the norm (read: G1), instead electing for more of a hybrid movie/Animated look. Starscream and Soundwave are the biggest examples, drawing a lot of complaints about how their ultra-lean, spiky bodies look "anorexic" or something to that effect, never mind that the designs actually complement their personalities quite nicely. Soundwave has it the worst between the two of them, with most folks being appalled at how he's not the bulky, square-ish bot he was in G1 and War for Cybertron.
History repeated itself with the first previews of Transformers: Robots in Disguise, where fans cried foul over the Art Shift from Prime's style to a brighter, more cartoony one, the intent of the creators to make the show more "fun" (even though Prime not being "fun enough" was one of their most commonly heard complaints), and the fact that Bumblebee is the leader of the main Autobot team, among other things. Furthermore, armchair critics came out of the woodwork to decry the new show for not adhering to the chronology of the Aligned continuity family (chiefly over the idea of Grimlock supposedly being a Decepticon)— many of whom were the same people saying that the Aligned continuity itself was a stupid idea during Prime's run.
The episode "That 90's Show" is hated by many fans entirely because it was an alternate backstory for Homer and Marge. This despite the fact that the show has never had anything even resembling continuity and has always operated on a sliding time-scale. What's even more ridiculous is that a lot of professional reviewers were actually getting away with massive amounts of Fan Dumb, like Robert Canning who literally spent four-fifths of the review bitching about this instead of the actual content of the episode, gave it a 3/10, and called it "an abomination". Simpsons' "continuity" is Serious Business. This is a massive exaggeration of the effect, claiming that it retconned away every past event established to have happened. If you accept that the show has a sliding timeline (which it very obviously does), the only thing this changes is that Marge went to college for a short time and Homer formed a band between them graduating and Marge getting pregnant. It also FIXED the massive plothole regarding the ages of the characters, as Homer and Marge supposedly had Bart right out of high school, yet they were 28 years older than him rather than 18. So it's more along the lines of: "They made their Expansion Pack Past and use of Comic-Book Time come with somewhat more obvious retcons and they've thus thrown out all other previously established past events, now it sucks".
The seasons when Mike Scully was show-runner (9-12) are often denounced as a Dork Age for simply being weirder than most. This also lead some fans to make the ridiculous claim other episodes were "realistic" instead of just not as strange.
In season 20 the intro was permanently changed for the first time since season 2 to go along with the show's widescreen HD makeover. The completely newly animated sequence features various minor characters and gags that weren't there before. Some fans hate that.
Ask in Latin America when the show turned bad. The answer will be when they changed the original voices in 2005, after season 15. This fact, almost unknown on the rest of the planet, is nearly a universal truth in the subcontinent. While few people know that the decline of quality began near or even before that point, due to new writers, directors or Executive Meddling, this is not associated with any other change than the voices that were replaced when, after Audiomaster 3000 (the series' original dubbing studio) closed, the new studio and the actors got into a conflict that ended in nearly all of the actors being fired. People can't take the current voice of Homer (Otto Balbuena), and recognize the real one to be in the voice of Humberto Vélez, a well-recognized Mexican voice actor. This is the same for the other actors who originally did the main characters' voices (Nancy Mckenzie as Marge, Patricia Acevedo as Lisa, Claudia Motta as Bart note Claudia started doing Bart's voice in the middle of season 9 after the original voice actress, Marina Huerta, left the cast due to a pay dispute, and incidentally, Marina returned to do Bart's voice after the conflict and Gabriel Chávez as Mr. Burns).
Toonami got a lot of this; fans themselves are a Broken Base as to whether it sucked when (in Toonami's last change in style) TOM received a childish look and a face instead of a helmet (being a robot, it was assumed to be his whole head), the AI character SARA disappeared with no explanation and was replaced with robots similar in design to the new TOM, and the setting was changed to a jungle planet outpost instead of the spaceship Absolution. Of course, there was a similar reaction way back when after TOM replaced Moltar... And the reboot of Toonami: while many people highly enjoy the new Toonami lineup many seem to think it sucks because it doesn't have nostalgia favorites such as Dragon Ball Z, YuYu Hakusho, Outlaw Star, and many others despite the fact that the rights to DBZ are owned by another network and the new Toonami has a limited that doesn't allow them to show every a bunch of stuff from the past along with new programming.
Because 4Kids redubbed and edited Winx Club, it got quite a bit of this reaction from fans. Many fans like to rage at 4Kids for changing the plot or removing scenes even though it isn't always that bad or important. Some changes were more generally preferred, however. On example is the hip-hop music used in the Halloween episode. Another liked change is with Stella, who was a stereotypical blonde bitch in the original, is a lot nicer and more likeable in the 4Kids version.
4Kids had a horrible track record of dubbing foreign shows to the point that they become stupid, make no sense, and have plot holes you could drive a truck through (see Dub-Induced Plot Hole). Scenes of character development were taken out of Winx Club or developing lines replaced with "funny dialogue" which is usually a string of puns and taking away all the drama. Some personalities were also changed to the extreme, the main one being Layla. Originally, she was a girl with insecurity issues due to her royalty life and wants to have friends, but 4Kids turned her into an extreme feminist who tends to act like a bitch.
There's also the fans who grew up with the 4Kids version who feel this way about the Nick version.
There exists certain parts of the fandom that are absolutely furious that in Batman The Brave And The Bold Batman's parents died when he was mad at them over a Christmas present. There is also the humor devolving Adam West-era puns, Batman practically having super strength, Batarangs being made of cellophane peeled from his chest logo (???), or Batman himself being voiced by Hoss Delgado making him even harder to take seriously. (Of course, this is more about this entire thing being based on the Silver Age.)
Family Guy: The most thunderous complaint about the show since its return to TV was its complete change in tenure and character. The program dropped its sit-com base and instead went for violence, grotesque imagery, overly long gags, Comedic Sociopathy, and in-your-fac political and religious commentary.
Many reacted this way when Mattel announced a tween Dora line to appeal to older girls. Many were expecting a Bratz-esque Dora.
Doug: Fans of the Nickelodeon version were and probably still are known to trash the Disney version, because the biggest change made to it was Disney making it now!
The changes weren't so bad, and the creators made explanations for the changes a part of the script. The show is set one year after the first series, so the characters are a year older, dress differently, have different hairstyles, different voice actors, etc., and the first new episode focused on Doug learning to overcome and deal with his fears of the changes in his life.
Though The Spectacular Spider Man was very well received by comic book fans and others, there are some of the more militant fans of the previous series who do not like the show for things such as the style, Shocker not being Herman Schultz, but Montana of the Enforcers, Venom's design, and probably a bunch of other reasons as well.
Ultimate Spider-Man received similar treatment from fans of Spectacular, who speculated that the show's very existence was the reason why Spectacular was axed in the first place. Once more became known about the series, other fans began complaining about the series not adhering to the comic book of the same name, as well as allegedly being very "toyetic".
Also, Spidey's Deadpool-esque personality and humour....though that criticism may be coming from forgetful and/or younger fans who don't remember that Spider-Man is the original and preeminent Deadpan Snarker of the Marvel Universe, and that Deadpool stole most of that schtick (other than Breaking the Fourth Wall) from Spidey!
Complaints were leveled at Green Lantern: The Animated Series for incorporating a lot of the more controversial elements from the Geoff Johns run (such as the Red and Blue Lanterns and the Star Sapphire Corps) despite starring the original Silver Age GL, Hal Jordan, and not any of the later Lanterns like John Stewart, Guy Gardner or Kyle Rayner. Early fan outcry was also leveled at the series for using CGI animation rather than the traditional hand-drawn style used in most other DC cartoons. And even the fans who liked the elements from Geoff Johns' books criticized the series for things such as the Red Lanterns not being mindless raging beasts like in the comic.
The Legend of Korra gets this from some fans of the original series who are upset that it has an entirely new cast and takes place several decades after the original ended, instead of directly continuing Avatar The Last Airbender.
Beware the Batman was already getting this when there was nothing more than two teaser posters being released, with Alfred using firearms proving to be a particularly controversial element. Additionally, some fans seem to take issue with Katana being used as Batman's core sidekick when Cassandra Cain, the Asian Batgirl, fills a similar function and has yet to be used in any DC television show beyond a non-speaking cameo in Justice League. And of course there are also animation purists who detest the use of CGI.
And let us not forget The Batman, another series that referred to him as "the Batman". A combination of having to live up to the Timmverse, character changes, weird designs, and the little matter of the Bat-Embargo turned many viewers against it.
Futurama had a rumored new voice cast that thankfully didn't go through, possibly due to fan reaction. Or maybe because replacing the entire cast would be really messed up.
The dispute was mostly due to the voice actors' salary demands, with numerous fans afraid and angry at the possibility of change demanding that Fox throw as much money at the actors as was necessary. Because who doesn't want to invest large amounts of cash in a series that had to be Un-Cancelled?
When the show was uncanceled for the first time, it immediately started getting wild accusations (even after the first two episodes of the season!) that the show was officially ruined just because the jokes were slightly edgier (the third episode in particular got a lot of this because of all of its topical humor).
Another problem that could be called They changed it, now it sucks or It's the same, now it sucks: In the last episode before cancellation, Fry & Leela had been made an official couple. After cancellation the show went back to the usual "Will they, won't they?" thing without explanation but it sometimes randomly had them being a couple for an episode without explantion.
Many people didn't like the idea of Batman Beyond where Bruce Wayne wasn't the actual Batman. As far as Spin-Offspring shows go, this series is easily one of the best examples of it being done right.
Ben 10: Alien Force got this reaction a lot. While the original wasn't a classic, apparently differences in opinion don't apply when it comes to declaring the franchise unsalvageable. Just look at the series page. While some of the criticisms are justified, others tends to fall in the Fan Dumb department.
Young Justice initially drew the ire of certain fans of the 90's comic book of the same name. Despite the fact that the creators said from the beginning that it would only loosely adapt elements from the book and that it would mostly do its own thing, fans still raised a massive stink. It got to the point where Peter David, who wrote the original comics, had to step in and tell people to calm down and accept that it was going to be good despite not matching his work. However, the drama more or less died down two years into the show.
There was also backlash over the Time Skip at the start of season 2, with a number of fans voicing outrage over the mostly-new cast and the apparent jettisoning of many of the originals (such as Aqualad becoming a villain and Artemis retiring). However a good deal of the controversy died down by episode 7, when at least two of the above-mentioned major complaints were addressed.
The Venture Bros. fandom went in this direction. The changes made for season 4 were mostly par for the course for a show with so much character development (every season has kicked off with some sort of major change) but Brock Samson's departure from the regular cast led to a vocal faction of fans declaring that the show is terrible without him.
To a lesser extent, Hank and Dean's revamped designs got this sort of reaction as well.
Strawberry Shortcake is prone to this due to the uncertainty of the direction each of the master licensees want to take the franchise which angered fans due to its frequent changes. When the 2003 version started, some of the older fans felt that the franchise was doomed. And when the 2003 version was aged-up in 2007, there was trepidation from some (particularly, fans of Honey Pie Pony, who weren't pleased that she had retired to Ice Cream Island permanently, and even then the send-off was only mentioned in a chapter book and not on the TV series officially, and after that the existing fillies, Honey Pie and Ice Cream Island was never mentioned ever again, while others who disliked the Pie-Man voiced their dislikes in the franchise bringing him back). Then there's the 2009 series, which were widely decried by the Slice of Life fans who're drawn to the series by the 2003 series being educationally wholesome as lacking in terms of educational content and emphasis on beauty over moral values, the transition to CGI, as well as being nothing more than a 30-minute toy commercial. And let's not get started on the 2009 series' announcements that Sour Grapes will be reinstated as the series' Antagonist...
There's also Shaggy & Scooby-Doo Get a Clue!, which was almost universally hated by the fanbase because of its drastic changes in animation and formula and mostly how it was just plain different from the rest of the franchise.
This has been going on with Scooby-Doo ever since Scrappy was added to the cast, and Velma, Daphne, and Fred were axed in 1980. A Pup Named Scooby-Doo also got a lot of flack back in the day, but is generally more accepted today.
Be Cool, Scooby-Doo! got hit with this almost as soon as it was announced, thanks to it having a far more comedic tone than its predecessor and giving the characters a redesign that people quickly compared to Seth Mac Farlane's signature artstyle. Much like Mystery Incorporated before it, some were eventually able to embrace these changes once the show premiered while others were not.
A lot of fans cried fool when Dwayne Mc Duffie, writer of Justice League: Crisis on Two Earths, said Superwoman—who traditionally is the Mirror Universe version of Wonder Woman—was one of Mary Marvel and said an underling was WW's counterpart. But then, said movie's original form was to originally bridge the gap between Justice League and Justice League Unlimited and a lot of fans felt Wondy did suffer from Adaptation Decay there. Kind of stupid when you realize that it was more inspired by the Grant Morrison story where Superwoman was Lois Lane. A number of Grant Morrison fans proclaimed that the movie was bad simply because it didn't adapt his arc panel for panel, despite only loosely borrowing from it.
Iron Man: Armored Adventures got some pretty heavy flack before the show even officially aired. The most common criticisms were that Tony Stark couldn't be Iron Man while he was still a teenager, and that the CGI animation sucks. Suffice it to say, most of the hate comes from fans who prefer the 90s series.
South Park: Where to start? There are fans that have long cried foul over the show's change in direction from its more surreal era to the political and current events-charged seasons, the changes in animation from more cartoony and crude violence to outright Gorn, and endless debates on whether or not these directions have worked. And then there are those that feel the show sucks due to the changes in female voice talent (which became a necessity due to Mary Kay Bergman's suicide): When Eliza Schneider left over a contractual dispute and her successor April Stewart took the job, one particular faction was not very amused.
The "real" death of Kenny at the end of season 5 and his replacement by Butters in season 6 ignited flamewars on the official site's forums and elsewhere. Following Butters' replacement with Tweek, it led to another debate over whether the show "sucked" now for changing the dynamic. All seemed well when Kenny returned, until he got put Out of Focus for Butters. But they've still thrown Kenny fans a bone from time to time, what with his role as Mysterion.
There are also a lot of fans who are fully aware that the Mirage Comics are the original TMNT version, but they still wish newer incarnations to be similar to the 80's cartoon because the 80's cartoon is the version that introduced most people to the franchise, being much more popular in the mainstream than the original comics ever were.
Even the 80's cartoon itself got some of this. Red Sky seasons, anyone?
The character designs of the 2012 show drew a lot of ire, even though at the time the 2012 show had not aired yet!
The Looney Tunes Show got a lot of this, mostly due to the personality change of Bugs, Daffy, and a slew of the supporting characters almost completely from their original selves; as well as the sitcom(-esque) style the show has in comparison to the original cartoons. The different art style of the characters also came under criticism, albeit to a lesser extent than the previous two.
Jeph Loeb announced that the second season of The Avengers: Earth's Mightiest Heroes! would contain 12 self-contained episodes. This stands in contrast to the fact the first season followed a serial format. Fans decided to hate these episodes before they even got to read synopses.
The addition of recaps to Disney XD airings necessitated a trimming of the minute-long intro. This trimming resulted in the replacement of the Ear Worm "Fight as One" with a speech by Nick Fury, as well as animation unique to the intro giving way to random episode clips. Fans wished for the reinstating of the longer opening, especially since Fury's speech sounds more like a promo for the movie The Avengers than a proper introduction to the cartoon, but the only consolation they received came when the last episodes of the first season came to DVD and Netflix with the theme song attached. Even then, Marvel probably attached it for consistency's sake, instead of fan appeasement.
Executive Meddling resulted in Spider-Man getting redubbed. The lines that JoshKeaton recorded for Spidey got replaced by readings courtesy of DrakeBell. Never mind the possibility that Bell's performance sounds fine on its own standards; a number of fans consider at least Spidey's episodes tainted.
There was internet outrage over Earth's Mightiest Heroes ending and being replaced by a new show, Avengers Assemble. Even before footage and plot details were released, some fans just seemed to hate it for not being season 3 of Earth's Mightiest Heroes.
My Little Pony fans did not treat the "Core 7" revision of the series nicely, especially when it came to Rainbow Dash; her accent changed, she became more generic instead of being a Cool Big Sis to everyone, and her catchphrase changed. In general Pony fans don't like changes to the series. G2 is often passed up in people's minds, and G3.5 has a Hatedom.
Some fans became very cynical after Lauren Faust left the show, with even the admins of one Pony forum (which will go unnamed) admitting they stopped watching it early in Season 2. This attitude mostly seems to appear amongst the earliest G4 fans, and given that the show's fanbase keeps growing it may be a case of It's Popular, Now It Sucks.
And then the pony wedding had to happen. It was way darker than the Season 2 premiere, a hypercompetent villain, and there was violence. It was by order of magnitudes darker than the premiere. The remaining Slice of Life fans who managed to stomach the premier left at this point.
Season 3 of the show had the number of episodes cut in half, but still managed to become the most controversial season of the show (Season 2, now being considered by most S3 haters as part of the "Good Old Days" with S1). The fact that a part of the show's status quo (the spoiler hidden below) being changed in the season finale only being the cherry on the sundae for either side didn't help much either.
Also, Derpy Hooves in The Last Roundup after Hasbro modified her voice, changed her expression to be less cross-eyed and removed Rainbow Dash's reference to her as "Derpy" after a Vocal Minority overreacted & complained about how her portrayal could be seen as offensive to persons with special needs. A good part of the issue was that while many fans liked Derpy, there weren't a uniting idea of her personality. Was she "ditzy with googly eyes, but otherwise fine", a female equivalent of Ed, Billy or Patrick, or an actual pony with special needs? As is the major problem with canonizing fandom created/inspired characters, not everyone could be satisfied and the fandom started to eat each other.
Alicorn Twilight Sparkle from the season 3 finale. If you're a brony and you thought the Derpygate controversy was bad... well, where to start? People left the fanbase over it, others threatened to do so, Lauren Faust (who, again, had nothing to do with this) got her Twitter flooded with people raging, and in general, the fandom was thrown into an uproar the likes of which haven't been seen since Han Shot First. The biggest complaints game from those who feared this would turn Twilight into a Mary Sue-type character... despite Meghan McCarthy, the show's head writer saying that wouldn't happen, and that many of the alicorns seen on the show aren't quite as powerful as fans make them out to be, and have been shown weakened or defeated before (we're looking at you Cadance).
The fourth season has Twilight being nearly exactly the same as she was before. Ironically, this caused a few complaints in the other direction. So little changed that some fans asked what the point of the change was in the first place. Lampshaded in "Twilight's Kingdom - Part 1" when Twilight herself admits that her new role as Princess hasn't really amounted to much.
Equestria Girls. The fact that the Mane 6 are humans (and Spike is a dog). That they have skin tones matching their pony coat colors. That they're all in high school. That they're all in dresses. That it's a kind of crossover with the main show. That it's a movie. That it might become a spinoff show. That, of all things, its intended demographic is for older girls and not the brony demographic (when the main show is mainly intended for young girls, but can be enjoyed by everyone, and the brony audience is outside its intended main demographic). It goes on and on... Has a bit of Irony and Hypocrisy to it since upon seeing the character designs, complaints erupted on how "Girly" the film is, and many Bronies are angry at haters for seeing the main show and assuming it is girly due to its name and character designs.
Fans complain that Bear wearing an unexplained flamboyant blue vest makes him look “gay”. Another complaint is that he doesn't need it since no one else wears clothing.
Many Recess fans reacted this way to Myles Jeffrey replacing Andrew Lawrence for the DTV movies (this was due to the latter's voice changing, though the former didn't even sound like him).
Arthur gets this anytime a voice actor is replaced.
Fans yelled this trope out loud when Oliver Grainger replaced the voice actor for D.W.
The worst offender is Justin Bradley, chosen to voice Arthur in season 6, whose voice was deemed too "whiny" whenever Arthur got upset, stressed or mad. He was later replaced by Mark Randall for home video releases and airings in America.
Cameron Ansell, Dallas Jokic and Drew Adkins are all criticized for sounding too female and more like D.W. than Arthur.
Alex Hood's performance of Alan "The Brain" Powers was also criticized for being higher pitched and whinier than the past Brain's.
The episodes produced by 9 Story Entertainment weren't taken to very well. The animation is very cheap-looking and slow compared to the previous seasons, and fans really hate Ladonna. What's worse is that the animation was switched to Adobe Flash after a total of sixteen years of traditional. However the more loyal fans of Arthur perceives these cries as being created by bronies to drag Arthur down since Marc Brown did not let the rights transfer to DHX when DHX bought up Cookie Jarnote DHX also produces My Little Pony: Friendship Is Magicand would viciously fight back.
Superjail's second season received quite a bit of this opinion from fans who weren't amused with the change in studios (Augenblick to Titmouse), nor the new animation or the change in writing format. Criticism ranged from the animation being too fluid and cartoony, the Warden becoming less sinister and more overtly childish, the writing being too wordy, and some feeling that the characters didn't need their backstories revealed.
The third season seemed to go over a little better with the fanbase, due to the staff's attempts at re-instating the wild angles and scene transitions within episodes. Although, there are those who continue to wish Augenblick would return to animating instead of Titmouse.
There are the fans that see Warden as having fallen in characterization even as early as after the pilot, which they felt portrayed him in the darkest manner.
The Twins becoming more visibly vulnerable, weaker, and not as involved in trouble as much as they used to be is another change that's gone debated, some deeming the characters to have been ruined ever since they were confirmed to be aliens.
While not a huge issue as far as criticisms were concerned, there was some annoyance about Kamala Sankaram and Melissa Brown not reprising their roles of Charise and Bruce for "Stingstress".
The Xiaolin Showdown revival, Xiaolin Chronicles, got this before it premiered. Most of the complaints stem from the fact that show was revived in Canada, meaning that nearly the entire cast with the exception of Omi and Katnappe had to get new voice actors. Another cause for complaint is the new names for the Shen Gong Wu, though the name change is justified due to the fact that the new producers of the show don't own the rights to the original Shen Gong Wu names. However, what is probably causing the most gripe with fans is the use of CGI in the showdowns, rather than the traditional 2D animation.
Pingu, after its cancellation in 2007, was Screwed by the Network in Britain by using Canada's Pingu marathon, which used HOT Animation's work as the outer bits, and using the original Swiss episodes without credits...WITHOUT CREDITS... and redubbing it with Marc Silk narrating. This annoyed many fans, especially those who used to Gag Sub the episodes. They will very quickly rage hearing Marc saying "Hello, Pingu!" or something. Some fans liked it better before HiT Entertainment bought the rights to said cartoon. Not that it needed narrating in the first place. What next? Jonathan Aris narrating Tom and Jerry?
Some fans of Steven Universe weren't happy when the show finally premiered and it carried a bit of a simpler art style than shown in the pilot and pre-release promo art.
With the fourth season of The Boondocks fans are starting to say this, because the season doesn't included the writing or direction of creator Aaron McGruder. Many claim his absence so far is very obvious as the clever social commentary and satire of the first three seasons are missing.
Star Wars: The Clone Wars (2008 series), while overall well-received by Star Wars fans (including Original Trilogy fans who disliked the Prequels) sometimes gets this reaction from fans of the 2003 micro-series just for being CGI or not made by Genndy Tartakovsky. It also gets this reaction from die-hard Expanded Universe whenever the series contradicts anything established in previous EU material (Ryloth's climate, Asajj Ventress's origins, the changes to Mandalorian culture in that time period, etc.) and that this series is actually part of official canon (as well as the de-canonization of the rest of the old EU) is pouring salt on the wounds for those fans.
Similarly Star Wars Rebels is receiving this reaction from fans of The Clone Wars for allegedly being the reason that series was cancelled and fearing that it won't live up to the standards of or be as dark as its predecessor (despite having some of the same production staff, as well as Greg Weisman as one of the directors) or suffer from Executive Meddling on Disney's part when the show wasn't even out yet. Even after previews were released, some criticize it for having a different art style from its predecessor. There are also those that just hate it for being part of Disney's new Star Wars canon, even when they hadn't produced any Star Wars works created under their name yet.
American Dragon: Jake Long got this reaction after the producers of the series revamped the series' animation with the debut of season 2, which also saw the radical redesign of several characters' appearances and for a style that was not as smooth nor as polished as that of the first season, which made the transition from one season to the next very divisive and at least for a time, resulted in a Broken Base for its fans.
Some fans of The Amazing World of Gumball weren't really too happy with the new voice actors for Gumball and Darwin in season 3. Justified, though, as their previous voice actors were hitting puberty at the time.
The month-long hiatus that Star vs. the Forces of Evil took during May 2015 resulted in the animation house for the series getting changed from Mercury Filmworks to Toon City. This did not go well with some fans, as the change in style is obvious to even the most cursory of eyes.
The 2006 revival of Biker Mice from Mars had quite a lot of detractors, mainly because of the character redesigns and the original villains Lawrence Limburger, Dr. Karbunkle, and Greasepit being Demoted to Extra in favor of the new antagonists the Catatonians and Ronaldo Rump.
The Simpsons: It's done In-Universe in the episode "Beyond Blunderdome". Everyone liked the original Mr. Smith Goes to Washington but Homer because Mel Gibson's character didn't use violence or action. Gibson actually AGREED with him, believing there was something wrong with the film despite the postive critical response. Once they changed the ending, everyone was in total disgust and booed at the new edit. (Well, that is unless you like beheading presidents, impaling evil senators with American flags, and killing everyone would the symbolism of anger.)