Yeah that’s not nice, and I’m glad you’d report it now, I’m sorry people didn’t stop him. Sometimes people do just freeze.
I can tell you though that my son (he’s in his 20s) has had harassment from women, sometimes in the street (once when he was just 17) and work. He’s quite a muscly guy and the number of certain type of women who think it’s okay to squeeze his biceps has quite astonished me. It does happen to men too, I didn’t realise the extent until it happened to him. And men often don’t feel like they can report either, or at least my son didn’t, he felt embarrassed. Like he’s meant to take it as a compliment??
Assault/harassment is never okay whatever gender you are.