Milo is effective because he fits into a marginalized segment of society, but holds traditionally conservative beliefs.
The liberals, the left, whatever you want to call them, don't know how to react to the guy because they don't understand why he isn't on their side. He should be "one of them", but he's not.
He's a mischievous attention whore, without question, but he's right on practically every point he makes, and if you're going to debate him with talking points and no real understanding of the issue, he'll rip you to shreds and make you look stupid.
You can dismiss him as a troll, but really all he's doing is exposing hypocrisy.
The idea that a flamboyant gay jew speaking at a university about free speech causes riots to shut down "hate speech" is pretty ridiculous.
If anything, it shows how far gone universities and their students are.
I think he's doing important work.