Socrates was also a professional troll. Should he (if he were not mortal) be barred from universities?
As for Milo, I've never watched him until yesterday. I saw a bunch of journalists claiming he supported pedophilia, yet refusing to quote him or even link to the video. So I figured I was being mislead (I was!) and watched the actual video.
While he is full of hyperbole, flamboyance and ridiculousness, he's also making valid points mixed in with it. For example, one of his major points is that the left wing identity politics is just a rhetorical weapon, not a real principle - that's why a "flaming queer" like him isn't allowed to hide behind it.