I am older than that old guy (nearly going on 78) and the way I think of it...if I cause shit, I expect to be treated just like anyone else and would not be angry that I was knocked down.
The only ones I do not allow that ANY violence is permitted is when the troublemaker is a child. There, we adults should know how to handle them without violence.
And your evidence that he started shit justifying that kind of reprisal is...