I'm not sure that "the majority" of Final Fantasy fans hated XII. Yes, there are people who dislike it, but it still sold well, there's a thriving thread on it here and many other sites. Also, not everybody played the FF series in order- I played X-2 before X and X-2 made me want to play X (that and having a conversation with the bloke in the local game shop where I kept popping in to see if they had any more FF games), and yeah, I enjoyed X-2 in a cheesefest kinda way. When I played X I was blown away, and although I prefer X to X-2, X-2 did not, in my opinion, ruin X in any way.
I also think you're wrong about 75% of fans hating Square Enix- it seems very high for a fanbase who love the games. If they hated them that much, they wouldn't buy the new games, however XIII sold well- I don't think that this is only 25% of the fanbase buying the game. If people hated the company as much as you claim, they'd boycott it. But they're still willing to try the games, meaning that their faith in the company hasn't been completely shattered.
I also think you're wrong about 75% of fans hating Square Enix- it seems very high for a fanbase who love the games. If they hated them that much, they wouldn't buy the new games, however XIII sold well- I don't think that this is only 25% of the fanbase buying the game. If people hated the company as much as you claim, they'd boycott it. But they're still willing to try the games, meaning that their faith in the company hasn't been completely shattered.