Michelle is supposed to be seen as a lovable Deadpan Snarker nerd that the audience is supposed to sympathize with because she doesn't have any friends. However, most of her screentime consists of her belittling and mocking people with a haughty and condescending attitude for no reason (especially considering that all other the students, aside from Flash, are pretty nice people who haven't done anything to deserve it), so it's pretty understandable why she doesn't have any. She thankfully improves greatly on this count in the sequel.
Tony Stark is shown struggling in his newfound role of being a mentor figure to Peter including looking out for his safety and wanting Peter to be better than him. Unfortunately Stark's personality quirks manifest throughout the movie as we see that he doesn't keep up regular communication with Peter, his face to face discussions are filled with snark, he consistently underestimates Peter's enthusiasm and desire to prove himself, and gives the Spider-suit mentoring protocols patronizing names like "training wheels" and "baby monitor". All of which add up to leave Peter and the audience feeling like Stark doesn't really understand him. Plus making it appear to Peter that he was not taking his claims seriously and didn’t inform Peter that he was passing information to the authorities that can take care of Toomes for him which led to the disaster on the yacht.
Avengers: Endgame: Steve Rogers, specifically at the end. The movie presents his choice to go back in time to be with Peggy as him getting the happy ending he deserves, but a substantial number of people saw this as selfish and irresponsible, as it essentially has him abandoning all the friends he made in the present and willfully ignore all the horrible things that happened to people he cared about (including Peggy herself) after past films pointed out he's the last kind of person who would do such a thing. Fans of Bucky are especially upset at what feels like Steve suddenly abandoning him after the main trilogy stressed the importance of their friendship and how much Steve regretted letting Bucky be tortured by HYDRA for decades, on top of Bucky explicitly being shown as saddened by the decision. The fact that the directors and writers had different interpretations of how Steve's choice affected the timeline doesn't help either, as the writers believed he created a Stable Time Loop while the directors believe he simply created an alternate timeline (both of which just opens up another can of worms full of Fridge Logic and Voodoo Shark). The latter interpretation comes with baggage as well, as it would make Steve a homewrecker (since, if Steve wasn't her husband all along through the Stable Time Loop, it means that Peggy may have married another man, depending on what time period he returned to). While the former interpretation would avoid that problem, it would also suggest that Steve just sat back and let all the horrible things that happened to his friends and the universe during the following decades happen despite having the knowledge to prevent it. Fans of Peggy weren't too happy either, as a big part of the premise of Agent Carter focused on her moving on with her life, and thus retconning that Steve inserted himself back into her life like that disrespects her character growth for his own selfishness, as well as essentially rendering her into nothing more than a trophy for Steve.
Spider-Man: No Way Home: Dr. Strange. He constantly blames Peter for the botched mass-hypnosis spell that triggers the movie's plot, but it's glossed over that he came up with the idea and he didn't properly explain the potential consequences before casting the spell or even talk to Peter long enough to find out what his real problem was and whether or not there was a non-magical solution to it (there was). There's only one brief moment where Michelle points out it's technically his mess, which he brushes off.
TV shows
Agents of S.H.I.E.L.D.: Jemma Simmons during the Framework arc. Yes, she is trapped in a world completely alien to her, and she is correct about the Framework being a simulated reality, and that everyone is running on limited time, but she doesn't even consider that to the people living there (whom she brushes off as just pieces of data) it is indeed very real, and her approach of just telling Mace and Ward - without any real proof other than her say-so, and expecting them to just believe, is a little frustrating. Coulson himself pointed out that Mace and the others didn't have his previous tampering to help him break through the illusion. She comes off as especially mean when she calls the fight against HYDRA, led by the resident versions of Jeffrey and Ward, meaningless, and her insults toward Ward also just seem to go into plain Irrational Hatred territory as this version of Grant Ward has shown himself to be a good enough man who genuinely loves Daisy/Skye and even apologizes for his deceased real-world counterpart's terrible actions. Also, when Ward makes the valid point that Jemma not letting him take the shot was what got Agnes killed, Simmons tries to justify her actions by saying the real Fitz would have never done it.
The Royal Family of Inhumans seem to have been intended as morally grey sorts, with a side of the murky politicking and good-things-for-bad-reasons inherent to being the nobles of a Crapsack World a la Game of Thrones. However, the fact that their main antagonist is Maximus, a revolutionary intending to end a gruelingly awful Fantastic Caste System where much of their society is slaves, while they're the ones who want to keep the system in place, makes them very hard to root for. Throughout the series, they come across as selfish, entitled, cruel, prejudiced, and smug, and have no scruples about hurting others or resorting to crime to get what they want. Their exile to Earth, meant to seem like a grievous fate, comes across as a fairly softball punishment. Their personalities and actions are too repugnant to seem like Noble Demons, and their goals are too self-centered to be Unscrupulous Heroes. At best, they're Nominal Heroes, and that's only because Maximus wants to invade Earth at some point and they don't (because Maximus wants to invade Earth for its resources, while the Royal Family's solution to the resource crisis seems to be to whip the slaves harder).
Some found Iron Fist (2017)'s Danny Rand to be this. He's suffered a lot and is trying to reclaim his identity, but the way he goes about it mixes naivety with entitlement. A standout moment is the third episode, when he angrily asserts his ownership of Rand Industries as something his father wanted him to have - in other words, declaring that he should be a billionaire by right of birth. He says that it's about reclaiming his own name but never tries to negotiate keeping that without the money and teams up with a cutthroat lawyer. The obvious Artistic License – Economics doesn't help, as in reality someone who's been missing for 15 years and been declared dead would certainly not be able to do this. When Colleen allows him to stay in her dojo he takes it upon himself to lecture her students uninvited, and proudly declares himself the Iron Fist even though by going to New York at all he's abandoned the duties of that role.
The title heroine can often come off like this. While she's clearly and understandably a damaged wreck of a person thanks to the traumatic experiences she endured while under Kilgrave'scontrol, she often comes off as a needlessly hostile Jerkass to everyone around her. Not helping matters was that the Arc Fatigue of the series dragged out Jessica's character development. And it really didn't help that the flashbacks showed she was almost exactly the same before she met Kilgrave, nor that the second season (which did make an effort to mitigate this) revealed that Jessica was always like this even before the car accident, despite Jessica's insistence that her closed-off personality is the result of traumas like Stirling's death and Kilgrave.
Many people also have professed to feel little to no sympathy for Jeri Hogarth in Season 2. Her ALS storyline is supposed to make her more sympathetic, but it doesn't change the fact that she is a supremely horrible person who did many cruel things without remorse in the previous season, and even in this one. Some even accuse it of being a Double Standard, since they doubt the narrative would have framed her as sympathetically if she was a man like in the comics. Thankfully, the writers seem to have realized this and Season 3 re-affirmed her as intentionally unsympathetic, ending her on the note that her dying alone and miserable from her ALS will be entirely her own fault.
For a while, it seemed that Kilgrave had a textbook Freudian Excuse: his own parents treated him as a lab rat and performed extremely painful experiments that, while giving him his powers, irreparably warped him into the sociopathicPsychotic Manchild he is as an adult. His parents were his first victims, with him using his new mind-controlling powers to enslave and eventually forced his mother to burn herself during a tantrum, leading them to abandon him. Then "AKA The Sin Bin" revealed that his parents were actually trying to save him; their experiments were to cure his neurodegenerative disease that would have left him a vegetable by twelve, thus turning them into people who, while still making a terrible mistake, were still fundamentally good people and didn't deserve their son's evil... except they still, you know, performed extremely painful experiments on him. That didn't change, and, if anything, the truth behind their actions makes those experiments even worse, since it means they couldn't be bothered telling him why or giving him painkillers like anyone with even a cent of common sense and decency would have done.
One does have to question if Jack Murdock ever considered the traumatizing effect his death would have on his recently blinded son when he set up his Thanatos Gambit. Enough that for Season 3, the writers had to go back and add a little more depth to his decision, to establish that Jack was a good but flawed man who made a bad decision rather than a heroic one.
Karen Page taking Ben to see Fisk's mother is often seen as a jerkass move on her part. Not only is it a severe moment that exploits his love of his wife and makes him think there's a new option for her (when there isn't at all), it put him in Fisk's crosshairs.
Karen constantly tells off Matt and Foggy for lying and keeping secrets, despite keeping some pretty big secrets of her own, such as that she killed James Wesley and lying about Frank kidnapping her when she really ran off with him.
At first, Foggy Nelson has quite a few legitimate criticisms about Matt's nighttime activities. But then he has the nerve to suggest that the real reason Matt wants to save Frank Castle from death row is not that saving a man's life is Matt's (and by extension Foggy's) moral and ethical obligation as a lawyer to do, but because Frank is a fellow vigilante... who uses methods Matt has made perfectly clear he does not approve of.
In Season 2, Matt has it when he's shown to be more interested in beating up bad guys than helping out at Nelson & Murdock (which the first episode shows takes on a lot of poor and underprivileged clientele), then showing more interest in hunting down the Punisher (who the audience knows only goes after criminals) than general purpose super heroics, then outright abandoning his law firm and friends for the rest of the season to help out his crazy and manipulative ex-girlfriend. While Matt does try to dissuade Elektra's attempts to invade his life, it's clear he's not trying as hard as he could and that she's very easily roping him into things with little prodding. He also doesn't find some way to tell Karen about Elektra, leading to him looking like a dumbass when Karen walks in and sees Elektra in Matt's bed, with no idea what was going on.
DA Samantha Reyes. Her mistakes during a sting got Frank Castle's family killed, and while it is implied she regrets this, afterwards she tries repeatedly to kill Frank simply to save her own career, acts like a complete bitch, and threatens to ruin the careers of three innocent, well-meaning people, plus her assistant. And yet we're supposed to feel sorry for her simply because her daughter was threatened. Few tears were shed at her death.
In season 3, all of the elements are there to show Ray Nadeem is supposed to be a sympathetic character... the relative with cancer (which has financially impacted him heavily), the difficulties at work, his family being terrified of the latest developments, and then being manipulated by Fisk. The problem is that the character comes off sort of shallow and bland, rendering these just a collection of cliches that have less impact than they would if he seemed a deeper or more thoughtful person; so when he makes arguments to get Fisk things he wants or goes around hassling Karen and Foggy because Fisk fingered Matt, he comes off as more of a jerk and a pest than a principled FBI agent doing his best in trying circumstances.
