Rejection by cisgendered people is a social problem. It's also their right to be bigoted and there's not much we can do about that. But assault?
Come on, once he crossed the line into assault, it was a crime. He was clearly the one in the wrong.
I could have understood (not approved but understood) if the guy simply said "um, not for me, I'm out of here." That's the ugliness of the transphobic social problem rearing its head. But as soon as he committed assault it was over the line, period.