The fact that PG answers DHH with another question to avoid the original question proves that he (PG) is uncomfortable with the subject. Though, this would better be asked to sama.
He's not avoiding the question. It's a stupid question. And this isn't nearly the first time dhh has butted heads with pg on Twitter (for no discernible reason other than to pick a fight).
DHH asks him if Thiel has invested more in Trump than in any other YC startup - implicitly asking PG if he's happy to have such a partner. PG retorts by asking if DHH would fire an employee who would be supporting Trump. How is that not avoiding the question?
I doubt it's even a question pg can answer though. I see it as pg getting to the crux of dhh's argument, without the foreplay. It helps show dhh's true beliefs. But sure, it is dodging the question.
This is a thing they have discussed before. If I were pg, I'd be bored with it by now.
