Yes, that's the point, he rather brutally insulted one specific disabled kid. I find it to be different from just telling a joke about a politician, for example. Can you publicly insult someone, by using a form of joke? I don't know, either. But the title sounds as if he just "told a joke" - that's misleading.
Remember Susan Boyle from a few years ago? The talent show star with the great voice who perhaps wasn't the most attractive woman in the world? Hundreds (probably thousands) of comedians have jokes commenting on her perceived ugliness. Was that hate speech? Should they all be punished for it?