We don't know if it worked because we don't know if a) that was staged or
Assuming that the video is not staged, it worked. If you don't like the video, i can give you other examples from Egypt.
There were a couple of famous incidents like that here, where the woman reacted like that, kept holding onto the man and wouldn't let go until the police gets there,
in the face of criticism from a lot of people standing by, urging her to "let him go" and stuff like that.
In those situations, things worked out rather brilliantly, and sent a clear, strong message to cowards who often engage in stuff like this. If it were to happen more often, i'd think it might reduce how rampant such assaults are.
b) the followed her afterwards.
That could happen whether she reacted like she did, reacted like how you think she should, or reacted in complete silence. Thus, hypothetical scenarios of how you think the scum may decide and get the chance to follow her afterwards do not invalidate the fact that she clearly put him in his place and ended the assault that was happening to her, in a most satisfying manner.
It was best for society an cowing though.
I don't think it was "justified" but it is not condemnable either. She had her well being as priority and thats how it should have been.
I realize you don't think it's justified, but i've seen no argument so far that helps me understand such sentiment.