White supremacist propganda and neonazi recruiting is what causes radicalization. Deplatforming those people is a good idea, yes.

Unlike what leftwing youtube and a few researchers from liberal universities would like you to believe though, Ben Shapiro, Jordan Peterson, Stefan Molyneux and conservative news sites are not radicalising people. There's no evidence for that.

It's not an argument against or for anything, it's a simple logical fact. Two things lining up logically doesn't mean there is causation, as there can be other things that also line up that could be an equally valid explanation. Finding causation requires actually looking for it, and doing some statistical studies. Of which I'm betting many do exist!