I have wondered about this, but the most I've come up with is that he is making a name for himself as a heterodox thinker. This would incentivize him to be critical of orthodoxies in medicine/higher education, and could explain why he takes some of the positions he has taken.

On the other hand, it seems that there almost zero medical professionals on the left who are interested in debating him and showing how he has been wrong about various topics. He calls for universities to host debates on these topics of public concern, but pretty much no one is willing to do it. This makes me think it is somewhat less likely that he is just completely wrong, and more likely that he is the one saying that various (naked) emperors have no clothes. I'm sure he's not always right, but much of what he says seems quite plausible to me (a fairly well-educated person with some understanding of statistics).

I'd love to know where folks have mounted successful critiques of his work, or if he has any conflicts of interest that he doesn't mention.