Hate is such a strong word. I think it's more like people in here 'dislike' / don't like him, not hate. And that's very normal.
And imo to be a fan favorite, there's more to a fighter other than skills, talent, and professionalism. People can see through a fighter. I think they recognize the skills/talent and respect him. His antics though, trash talking (that often involves sexual content), making rape jokes to Holland, making jerking off gestures to Costa's coach after the fight is over, and then saying he's doing it for those who are bullied after acting like that? Those things, and imo that seems to be kind of ironic.
I mean GSP for example was bullied in the past, but what did he do in return to the bully when they crossed paths after years? He forgave him and gave him a job once he became a star. He didn't let that dark experience carry through on how he acts as a MMA fighter all throughout his career. I mean it's those kind of things that people see through that makes people love you.
And as for the people here, they know he's a great fighter. I think they're just not a fan of how Izzy acts and carries himself especially after a victory and when he's on top and the highest of highs. Even if he only does that to sell and make people watch him. I don't know much about him and I'm not judging him. I respect his skills, but not so much on anything else. I picked him to win tonight, and I'm not much of a fan. And that's just how it is.