> Let's assume for a moment that the target of these pejoratives was an alt-right troll

Do we know that it was?

> Do you find this interpretation implausible for some reason?

I do but that's because, taking all the interactions I've had with his output into account, I'm not given to charitable interpretations of his intentions.

> Can anyone offer a better one?

Yes, he's happy to use casual racism and homophobia until someone calls him out on it then he backtracks to claim it's satirical. But what you really mean here is "can anyone offer a better one that I agree with" and I suspect the answer there is no.