While the series had slowly been adding more action elements as early as Resident Evil 2, it was Resident Evil 4 that set the series on a far more action-packed course as opposed to the Survival Horror genre that it had pioneered. It had downed enemies dropping ammo and other loot for the first time, allowed players to use that loot to upgrade and purchase weapons, downplayed the puzzles and exploration, replaced the zombies with the comparatively human-like Ganados, introduced quick-time events, and featured scenes of Leon suplexing and spin-kicking enemies and leaping through a laser grid in a manner that would make Keanu Reeves proud. Furthermore, as this retrospective by Foxcade points out, the final third of the game turns into an adrenaline-fueled thrill ride as Leon reaches the Big Bad's island fortress and starts fighting Ganado soldiers, with the Gothic Horror atmosphere of the village and castle segments mostly fading into the background in favor of modern laboratories and industrial facilities. While these changes were divisive even then, RE4 was still scary enough, and retained enough of past games' horror/exploration DNA, that longtime fans could ignore them and appreciate the much-needed improvements to gameplay that it made. It's not too controversial within the fandom to list RE4 as one's favorite RE game.
However, the next "main" installment, Resident Evil 5, took these changes even further and started bringing the series into Third-Person Shooter territory. It featured nearly non-stop action, emphasized the enemies' numbers and power for its scares, gave players abundant ammunition supplies that made ammo conservation a much more minor concern (and thus reduced tension by making enemy encounters far easier to plow through), removed the exploration of past games in favor of a more linear progression, and featured over-the-top Action Hero protagonists — a shift that was met with a mixed reception from fans and critics. The following game, Resident Evil 6, as well as the spin-offOperation Raccoon City, were full-blown action shooters and low points for the series, at least from the perspective of longtime fans and critics.note RE5 and RE6 were much better received by more casual fans, to the point that they are not only the top-selling Resident Evil games, but some of the best-selling of all Capcom's games; as of February 2020, they were 2nd and 3rd on Capcom's top 10 games list, with the more fan-acclaimed RE7 and Resident Evil 2 (Remake) being 4th and 6th respectively. Furthermore (as argued here), RE's transition from horror to action wound up impacting the entire survival-horror genre, especially at the big-budget levels, as games like Silent Hill: Homecoming and the Dead Space sequels imitated it. Some have even called RE4, in the long run, a Genre Original Sin for survival horror, if not an outright Genre-Killer. Fortunately, Capcom eventually realized that the series was going the wrong way, creating the Revelationsspin-offs and later Resident Evil 7: Biohazard that brought gameplay back to a focus on exploration, ammo conservation, and scares, while still retaining the gameplay innovations and weapons upgrades of the main series games.
Another, and earlier, Original Sin is the film adaptation, which was, at the time, one of the most action-packed zombie movies ever made, and certainly more action-heavy than the games that preceded it. Its sequels only further amped up these elements, to the point where the RE movies came to be described strictly as action films with zombies in them. The success of the film series likely colored people's expectations of the games, leading to later installments of the latter, starting with RE4, incorporating more of the former's stylistic elements.
An example from early in the series was the Solve the Soup Cans puzzles where you have to get specific items to open doors. It made sense to have trick walls and doors that need special keys in the first game's mansion, which was deliberately designed by an eccentric to be a death trap. It makes less sense when such puzzles are occurring in the middle of a populated city, such as the infamous example in Resident Evil 3: Nemesis where you have to find a statue to place on a plinth in the middle of a park, which makes it turn to reveal... a car battery. In the middle of what should be a normal city once again. Even that was tame compared to Resident Evil Code: Veronica in which there were tons of soup can puzzles left, right, and sideways almost at the very start of the game. Starting with 4, it became less gratuitous (to the point where some fans felt that there were too few puzzles), though you still might wonder why you need to collect a bunch of emblems to open specially locked doors in a Spanish village.
In addition to their focus on Action Horror over Survival Horror, Resident Evil 5 and Resident Evil 6 were also slammed by many for having bizarre, unrealistic plots that were described as reminiscent of B-movies. This particular sin goes all the way back to the very first game, whose own plot was equally bizarre, unrealistic, and ripped straight from a B-movie. Such bizarre "a corrupt corporation is performing illegal bio-weapon experiments that have gone wrong and released zombies & monsters!" plots have literally been the Resident Evil series' staple since its inception. The difference was that, back then, the camp was intentional. The early games were meant as homages to Western zombie B-movies from The '70s and The '80s, as evidenced by the first game's (in)famousFull Motion Video intro. Even as late as Resident Evil 4, the series still tried to occasionally wink at players with its over-the-top villains and Evil Plans. Once later games started boosting the production values and going for a more serious tone, however, those campier elements stuck out like sore thumbs and started dragging on the genuine drama that the games were trying to go for.
Resident Evil 6's biggest problem, the multiple storylines with different tones, was done in Revelations first. The difference is that, unlike RE6, the ones in Revelations aren't drastically different. Even the more action-packed chapters are still at least horror-adjacent at the worst, and instead focus on a different type of horror (being overwhelmed, being injured, so on and so forth), and they're all short by virtue of (originally) being a 3DS game. Plus, even with those, the game is predominantly about Jill and her partner, with the brief sections of other playable characters adding to either her part of the game or the overall plot rather than demanding equal attention.
An oft-mentioned criticism of Resident Evil 2 (Remake) is how the A and B scenarios are largely incompatible with each other, that is events that could only happen once (like the deaths of certain characters) happen in both, making it impossible for them to be canon with one another when they're supposed to be running congruent to each other. However, this was actually the case all the way back in the original Resident Evil and its remake, where the canonical events of the series state that Chris, Jill, Barry, and Rebecca explored the mansion while there is no game mode or ending where that takes place — even in the proper best endings either Jill and Barry explored the mansion while Chris was captured and Rebecca was never seen again, or Chris and Rebecca explored the mansion while Jill was captured and Barry was never seen again. The biggest difference, of course, is that the A and B scenarios in the original Resident Evil 2 actually were congruent with one another and this was a beloved feature of the original that doubled the replay value, as the B scenarios in the original were treated as a New Game+, leading to the remake drawing much harsher criticisms for this than other games.
Resident Evil 3 (Remake) took a lot of flak for feeling like a Mission-Pack Sequel, especially in comparison to Resident Evil 2 (Remake). The thing is, the exact same criticisms were leveled at the original RE3 itself when it first came out twenty years prior. At the time, fans held that it was too short, what with it only having a single campaign versus the two that RE2 offered, and didn't really offer much new for fans of the series. For a while, fan consensus actually held Resident Evil Code: Veronica to be "the true RE3". The difference between the original RE3 and the remake is that the remake had two games — the original RE3, and the RE2 remake — to live up to instead of just one. While the original RE3 was similar to its predecessors on the surface, it also introduced a number of new gameplay features, such as Story Branching, ammo crafting, the quick turn, the emergency escape, and the Mercenaries bonus campaign, that added more strategy to the series' Survival Horror gameplay, while the RE2 remake added new areas, weapons, bonus campaigns, and other content that the original lacked in addition to thoroughly modernizing its gameplay. The RE3 remake, by contrast, actually removed some areas and features from the original game (the clock tower, park, and factory levels, the branching paths, Mercenaries mode, most of the bonus outfits) while having much the same gameplay as its immediate predecessor, leading to unwelcome comparisons.
Resident Evil 5 marked a drastic Tone Shift in the series, with earlier games all relying on being deliberately cheesy and ridiculous to both pay homage to the B-movies they were inspired by, but also avoid taking the wacky plot too seriously. RE5 completely changed that. Gone were the ridiculously quotable one-liners (aside from Wesker's memorable dialogue) and goofy set pieces like outrunning a giant statue. The story and characters are both extremely somber and the subject matter is taken with complete seriousness... which only further highlights how ridiculous it is. However, 5 was still a good enough base game (with, as mentioned before, Wesker's memorable performance) and fans expected that sort of stoic machismo from its hero Chris Redfield. The problem was, this tone shift remained in every game that followed, not only making the story overly melodramatic, but also affecting previous protagonists' personalitiesnote Leon being the most egregious offender. He went from a snarky, witty ladies man who had a joke for every occasion to being a morose, stoic "badass" that is indistinguishable from Chris Redfield except by his slightly more pretty-boy looks.. The lowest point is generally considered to be RE6, where the combination of poor plotting, bland characterization, and the games taking themselves way too seriously caused a perfect storm of badness that left fans greatly displeased. While the shift is still not completely gone, 7 and the remakes were both scary and enjoyable enough to make fans more receptive... although there are still plenty that miss the old days of "Jill Sandwich" and "Where's everyone going? Bingo?".
One of the most common criticisms of the films concerns the character of Alice, a superhuman Action Girl who serves as the main protagonist of the series, with many detractors accusing her of being given New Powers as the Plot Demands. All of the elements about Alice that were criticized in those films could also be found in the very first one, generally held to be the best of the bunch. The difference was that, in that film, while she pulled off ridiculous She-Fu like roundhouse-kicking a zombie dog in the face, it was still roughly within the bounds of what was realistic, meaning that her actions weren't too far off the scale compared to the cast of Badass Normal commandos surrounding her. It also helped that, unlike later films, the first Resident Evil film did not feature any characters from the video game series for Alice to make look bad. It was only in the second film, Apocalypse, where she was both made explicitly superhuman and paired up with characters from the games, at which point the problem became a lot harder to ignore.
As noted in this video by Ryan Hollinger, Paul W.S. Anderson was, at the time, a surprisingly logical choice to direct the first film. He was known for making pulpy B-movies, which squared up perfectly with the tone of the games — and that was exactly what he delivered, diverging from the finer details of the games' storyline but nailing their tone. When the first film became a hit, he was given an Auteur License on the rest of the franchise, which quickly became a Vanity Project for him and Milla Jovovich (the series' lead actress who married Anderson after the first film) that brought out his worst tendencies as a filmmaker.