For more good examples of many of your points, see Hitchens e.g. 4:30. If you feel like reading something taboo today, I would recommend the old apologetics for American slavery. Some of them are really good: will black people be better off as somebody's valuable property or as a competing source of poor labor? Who here really likes black people? How do you think they'll do when they are "free"? We can give a half-shrug to the paternalistic crap, but we can't shrug away what happened after Reconstruction ended.
All that said, David Friedman is disastrously wrong.
Should we never hire a slavery apologist for a professor? No, we should still require ourselves to think. Should it be counted against an applicant? Yes, and heavily. I promise to explain, but first, "diversity".
If you can't recognize the distinction between "let's not fill the room with old white dudes" and "any diversity is good for its own sake", I can't help you. (If you really need me to, I will argue why the examples of diversity in the first paragraph here matter.) Not all representation is good. We all know it isn't good to have "both sides" present. It's perfectly reasonable to marginalize viewpoints that are really, really stupid or really, really abhorrent. Yes, we have all sorts of biases that make such assessments risky, but that doesn't make such assessments worthless.
Sometimes going far out of one's way to really understand the opposition makes you much better than never trying the exercise. Since we typically do too little of this, we should emphasize it. But it is almost always a complete waste of time. I would be better if I could articulate the arguments for 911 truth as well as any truther could. I would be better if I had memorized James Randi's library of quacks and cranks. But not much.
Modern diversity efforts do lead to unwarranted censorship. Duh. But if anyone here thinks that academia is less open and diverse now than it was 50 years ago, please recommend a source.
Saying terrible and false things should count against you. I don't like racism. Racism is bad. Marginalization in media, social life, and institutions is effective against it.
Saying terrible and false things should count against you.
How do you know the thing is false if you systematically censor any arguments for it?
I don't like racism. Racism is bad.
Taboo "racism".
Related: Heuristics for Evaluating the Soundness of the Academic Mainstream, Admitting to Bias, The Ideological Turing Test