He didn't insult the fans, he insulted the ultras. There's a big difference.
The fans go to games to watch the football, to cheer their team on and to enjoy the game.
The ultras go to games to pick fights with opposition fans, to hurl abuse at each and every player, often throwing racist abuse at black players, and in general do nothing but cause problems for the genuine fans.
Absolutely nothing wrong with what he said. And either way you think he's the most scummiest footballer despite all the adulterous, rapist, wife beating, racist, drink driving footballers?