The hate campaign started a month before the game even released, the majority of metacritic score game asap when it was humanly impossible to have beaten the game.
I'm part of some gaming communities on facebook and a lot of people still can't handle a woman being as strong as Abby was, even as she trained her ass off like a maniac for her revenge.
The reason behind the hate campaign was just one: blind hate.
I've already stated exactly what the issues with the game were. You didn't address a single one of them, and bring up the irrelevance of Abby's body structure. I didn't once mention it because it had nothing to do with why the game was bad. Four or five people not being able to handle muscular women is not the same thing. There's no reason to even bring that up as a part of the conversation. Of course, there's blind hate but not to the point you're speaking of. Because if you have to bring that up, you have to bring up Ellie's sexuality too. It's not a big deal, not everyone has to be the same, and it's fine. If you have a problem with Abby you no doubt have a problem with Ellie too, and I don't see you mention that either.
I've heard people say, "I don't use females in games." And you know what? That's fine too. Some people just don't like playing characters that aren't like them. But I've already said my issues with the game, and it had nothing to do with my expectation of how women should be treated in games. If it was really that bad, the first game would have failed.
Abby's set-up was done entirely wrong in the game. You have to make a character be legitimately likable if you want her to kill Joel, and that's not what happened.