Trying to killed your former team member is evil and also being apart of a terrorist group is also pretty bad.
In-universe, outside of those dead samurai, nothing Sasuke did couldn't be framed as being him undercover a la Itachi. Leaving the village to join with Orochimaru was to eventually kill him, finding Itachi's for the Uchiha Massacre was something no one blamed Sasuke for (we even seen people praise him in-universe for finally killing Itachi), and Danzo after the Kage summit was a serious liability to Konoha (moreso than before) so him dying was the best thing after how the other Kage's reacted.
Hence why I said "to anyone not knowing the full story".
From a readers perspective, sure. There was a bit in the Kage arc where Sasuke inexplicably went crazy and tried to murder everything in his path, but it wasn't like it was worse than the other thing we seen other characters in this series do.
Killing your team members/allies is pretty evil... but people seemed to think highly of Garaa and Neji despite the former having murder his countrymen and made his siblings shit themselves, and the latter having nearly killed Hinata. So it wasn't really evil so much of a "misunderstanding".
Being a part of Akatsuki is bad ... but so was apparently a punch of people who were actually decent people or in a super undercover mission to infiltrate the organisation.
The thing with Sasuke is that to him, everything from leaving the village up to the Kage arc was doing whatever it took to get to Itachi without becoming the same as him. He refused to kill Naruto after their fight for that reason, he went ahead and freed all those experiment subjects of Orochimaru because of not wanting to kill anyone other than Itachi. That fit with how his character arc ended up playing out in the end, as being someone who had something terrible happen to him and doing his best to make sense of it. You will notice that throughout the manga Sasuke had been noted to not having killed anyone or saying he won't kill anyone since leaving the village. Even when dealing with the White Zetsu's, Sasuke noted he could kill them before dealing with Naruto.
The Kage arc sort of screws with that a little, but Sasuke isn't the last ninja in this world who did something crazy that ended up being brushed off as being part of a problem with the Ninja world as a whole rather than himself.