I have seen the video many times and have formed my opinions. He did nothing but hold her back until he was punched in the face (apparently despite the fact that she couldn't reach him).
Was she going to win the fight? Of course not. Was what he did right? Of course not. But to say she was no threat whatsoever is false as well. The guy was punched in the face... the threat was her balled fist and threatening words... the actual punch made good on the threat.