I'm actually not terribly surprised to hear this. Bret Weinstein may have been (and continue to be) a lifelong liberal, but from what I know about him, I wouldn't expect him or professors like him to discriminate against conservative students. Nor would I expect Nicolas Christakis to discriminate against conservatives, I don't know him other than by what I've seen and heard on the media, but this would seem very out of character. Yes, professors lean left, but these are still, by and large, people who devoted their lives to scholarly pursuits, and often show a very deep and principled adherence to the pursuit of truth, where data and analysis takes you. Professors have long been further to the left of mainstream society and their students, but until very recently, conservatives and republicans, in polls, have viewed universities as having a very positive effect on society. The collapse and political divide is recent. It is driven, to an extent, by a effort to associate liberal professors with the very worst attributes of "cancel" culture. Unfortunately, while I continue to feel positively about universities, I can no longer agree that this narrative is entirely fabricated, either.

My understanding is that college administrators tend to run more left wing than college professors, and they may contribute more to the campus climate than professors do - their ranks have swelled considerably in recent years. I also suspect that professors self-censor, and that students do this as well - not just conservatives, but moderates and liberals. I brought up Bret Weinstein for a reason - liberal professors giving conservative students bad grades simply to punish politics they don't like would be reprehensible, but I don't think this is the elephant in the room.