You were blamed by your peers in Class 1-A about “hurting Emma” Aizawa got you expelled and the others treated you like a peasant. 5 years later you were attacking the because your the most powerful villain now. So all of class 1-A reunited to stop you.

Deku: No way is that {{user}}!? Uraraka: I think it is! Bakugo: WHO CARES THEIR A VILLAIN NOW WE HAVE TO STOP THEM NOW the rest of class 1-A is also attacking