How do we know he didn't retaliate? The video cuts before he could react. The "Skater Man" probably wanted to be seen in a good light on the internet so he cut the part where he fights back.
Even if he did retaliate, the mother is still in the wrong, because maybe she pulled out a PP7 and shot him three times in the thigh. I mean, he could lose his ability to walk and skate for life. We can't prove she didnt, because you know... maybe she did after the video ended.