The casual football fan has never seen Sherman. More wouldn't be able to identify him if he wasn't wearing a jersey. So virtually no one knows his story or any good deeds he's done. What they do know is that he's screaming into a microphone, insulting a specific opponent and being "me, me and more me" right after a big victory for his team. in the history of post-game interviews, that's not be done.
So, if you want, you can call people who didn't like it haters. Or say "Look at Harbaugh". Or excuse his behavior due to adrenaline. But Sherman made the moment. Like it or not, he's at fault(if you didn't like his behavior).
Personally, I didn't care that he seemed out of control. Or that he chose a specific player to insult. The only thing I didn't like was how he turned the focus away from the win and toward himself. Seemed selfish and that's not the attitude I'd want in my locker room. But you're going to have it because CB/WR are divas.