He's a psychology professor who happens to take a dim view of the prevailing narratives on gender studies and their real world implications.
He became famous when he refused to comply with a law which could have been interpreted as forcing him to use gender non-binary (i know) pronouns. His position was that if asked by an individual student he would refer to them as they wanted, but would not be mandated to by the state (Canada).
So then that caused a storm with the SJWs which they must now regret as it catapulted him into the public eye. He started releasing youtube content related to the issue and became popular with people disillusioned with SJW leftism (me) and also unavoidably, the alt right.
So then he becomes an alt right weapon against the SJWs, who in turn perceive him as a nazi. The guardian considers him to be a misogynist because lots of men listen to him and he opposes the SJWs, etc etc, culture wars.
Aside from all of this, he has loads of videos on YouTube with really good advice for young men about how to find meaning and be useful members of society - but the SJWs and Alt right cant politicise that so no one cares. Thats what he is really about though.
EDIT - he was also the intellectual source of the Google controversy with James D'Amore, which is what ultimately had me branded as a misogynist and a nazi.