I think he gave up on trying to get a debate victory, so he is trying to get you to lash out to get a "win", like women do.
I've asked him privately if I've done something to offend him. However, he says that him publicly attributing ungenerous motivation to the things I say and egging me on is because he himself prefers friends like that. However, I don't believe he truly likes it if people gang up on him publicly and insult him.
I think he's smart and original in many ways and he was friendly towards me for years. Not sure what happened. Anyway, I have boundaries and since he's back to rhetorics instead of honestly addressing the issue, I'm through.