He might be of the left, but I don't know that it is a pretty good possibility. The guy might be a radical right-winger, and radical right-wingers can show up anywhere, even here in Big Shoulders, the right's platonic ideal of a leftist communist socialist hellhole, yet 17% of voters here went Trump in 2020. Location alone is not evidence.
I'm skeptical of the implication that because someone lives in a city or goes to a college, that constitutes de facto evidence that they must be of the left, and that if an incident of antisemitism is present, then by extension, that means the left is just as antisemitic as the right. I won't buy that until I see something more concrete than, it happened at a college.