Supporting Trump isn't some weird mark of shame or anything; it's not my point that he's worth dismissing because he tolerates Donald Trump. Rather: he's worth dismissing because he has practically no interesting perspectives. He's a US-style right wing conservative in the most conventional possible sense. That doesn't make him a bad person, but it does make him a weird topic for an HN discussion.
Later
You expanded your comment (which is fine, so did I!) and I just want to say: I'm not so much interested in debating the merits of Sowell's positions --- which would make for a boring political argument --- so much as just recognizing that he has them, and that they're the standard-issue intellectual uniform of 1990s American conservativism.
If you want to rebut the point I'm making, I think the most effective way to do so would be to spot some position Sowell has taken that is far outside the mainstream of the Hoover Institution. Then we'd be discussing what makes Sowell interesting, rather than relitigating the most boring debate in American politics.