A likable protagonist can sometimes be the key to success in a story, allowing fans to care about this central character's story, struggles, and development. It's not always a cakewalk and some protagonists walk a tricky tightrope where one wrong move can make them despised by the whole fandom. Sword Art Online's Kirito is one such protagonist.
While Kirito didn't start out disliked by most, viewers came to find the character as one of SAO's many weaknesses, whether it's due to his personality, actions, or development. That opinion has persisted across this controversial franchise and doesn't show signs of slowing down any time soon.
10 Kirito's "Female" Avatar in GGO
During the "Phantom Bullet" arc, Kirito went undercover in the game Gun Gale Online with a new avatar that turned out to be ultra-rare and, of course, handed to Kirito upon entering for the first time. On top of that, for some reason looked more feminine than usual, which made many players mistake him for a girl.
Kirito decides to pretend to be a girl, or at least whatever he thinks being a girl is, leading many of his fellow players on until this lands him in hot water, as he sees Sinon stripping. The way in which Kirito decided to keep a low profile not only ends up being unnecessary while backfiring, but the way it's presented also comes off for the sole purpose of genderbending jokes.
9 Cringe-Inducing Attempts at Making Him Edgy
There have been more than a couple of moments, especially in the early episodes of season one, where it appears the series tried to make Kirito seem edgier than he actually was. Examples include the despair of losing the Moonlit Black Cats or when he decided to shift all the beta-tester hate onto himself, but some of these come off as more cringy than edgy.
That last instance is probably a great example as he decides to label himself as a "Beater" (beta-tester and cheater), which he tries to make sound cool, but it really isn't. Despite all the attempts though, none of these things stick to Kirito in the long run, so they kind of mean nothing.
8 Being Constantly Embroiled in Controversial Moments
One thing that makes SAO so controversial outside of divisive opinions is the scenes where female characters are sexually assaulted, and to say the anime handles the subject with grace would be wrong. And just about every time it happens, Kirito seems to be right in the middle of it, ready to stop it.
Now Kirito stopping sexual violence like this isn't a bad thing, the issue is that these moments exist not only to be dark for the sake of darkness but to embolden Kirito's character by making most other men (outside of Klien, Agil, and Eugeo) around him creepy perverts. Basically, these moments are framed as an outdated male empowerment trope for Kirito and that is problematic in itself.
7 His Anti-Social Tendencies Got People Killed
At the beginning of the Aincrad arc, Kirito would mostly prefer to do things alone, keeping his level and status as a beta-tester hidden from the people around him, given the stigma towards them. In actuality, though, it's these anti-social tendencies of his that end up getting even more people killed.
Given how poorly defined the beta-tester hate is, there's really no reason why he couldn't share what he knew about the game with others to help them, yet he kept this and his high-level secret from everyone which ends up getting multiple people killed by Illfang and ends up being half the reason the Moonlit Black Cats get killed.
6 The Constant "Soapbox" Speeches Got Old
It seems that not only must Kirito always win, but he must always be right too. Throughout the course of the series, Kirito makes quite a number of speeches/monologues on certain themes and subjects, most notably the "real world versus the virtual world" argument, which ended up getting kind of old pretty fast.
The intent was probably to make the character seem enlightened by his experiences but end up coming off as shallow attempts to make Kirito seem philosophical. These topics have layers and are open to multiple perspectives, but the way Kirito presents the argument and the way the anime follows up on it seems only in service to make him look correct.
5 Nobody is Allowed to Progress Without Kirito
Being the central protagonist of the whole series, of course, characters around Kirito are going to be influenced by him or his actions. The problem seems to be that their development is almost always tethered to Kirito at all times. Rarely, if ever, is anyone in SAO's supporting cast allowed to progress on their own terms without Kirito shaping it in some way.
Pretty much all of Kirito's friends are like this, from Asuna, Lisbeth, Leafa, Sinon, even Eugeo and Alice develop because of his word or his actions. It's okay to have a protagonist effect or inspire the people around him, but for SAO, it's as though everyone is helpless to do anything or be anything without Kirito.
4 A Lack of Any Kind of Personality
The mark of a good protagonist can sometimes be the way in which their personality comes off to the viewer, whether that makes them relatable, charming, or just likable. The issue many have had with Kirito in this regard is that he actually doesn't have much in the way of personality, with very little that actually motivates him, or even flaws.
Outside of being a gamer and a tech nerd, Kirito doesn't have any notable personality traits and comes off as a generic kind/heroic protagonist type. Apparently, some of the light novels gave him more of a socially awkward side, however, the anime pretty much ignores that, leaving Kirito as kind of bland at best.
3 He Basically Gets No Character Development
It seems that a lot of SAO's characters are only allowed to develop up to a certain point and then mostly become stagnant, and sadly Kirito is a prime example of that. The most development Kirito gets is in the Aincrad arc, where he goes from keeping people at a distance to learning to rely on others again, and some slight trauma from the death game. And that's about it.
For the rest of the series, Kirito remains pretty much the same as a character, not really changing or growing in any meaningful way. The events of the series from Aincrad onward are just things that sort of happen to him but don't have an impact on his character as a whole.
2 He Slowly But Surely Became a Harem Protagonist
Kirito has surprisingly good luck when it comes to attracting the attention of the ladies, whether he intends to do that or not. Despite being in a strong relationship with Asuna, Kirito has grown a large following of admirers who will follow him to the very ends of the Earth. Essentially he became a harem anime protagonist.
While some harem anime can have decent male leads, Kirito came off as one of the lesser examples, where girls flock to him and he doesn't seem to notice the intensity of their affection for him. It also makes these characters seem cheap as their world practically revolves around Kirito. This even extends to his own sibling, which is gross for a number of reasons.
1 Becoming Overpowered, Good at Everything, & Practically Untouchable
To address the giant digitized elephant in the room, Kirito's most infamous trait is how overpowered he is. From the start, Kirito was a step above the rest, able to take on anyone without getting barely a scratch on him and as the series went on, he would get even more ridiculously broken abilities.
There was just no tension around him since Kirito was practically untouchable. As a result, many viewers saw Kirito as a boring protagonist to follow because he was good at everything and never really had to struggle much to achieve what he wanted, labeling him as a "Mary Sue" character.