I graduated in 83. I could not tell you the political ‘gender’ of most of the teachers I had. Some of them were likely flaming leftists. But it sever showed in their classes. The best teachers I ever had wouldn’t even discuss politics unless it was part of the class and even then they were as neutral as possible. And that was a mere 30ish years ago. Small towns haZ their advantages.
I would like to see the school in America that now applies to. I doubt one such place exists.
By and large, most of my profs were decidedly leftist and a few outright communists. They didn't all wear their politics on their sleeves, but many were not shy about it. Some of them were really obnoxious jerks, but most were decent people outside of their politics.
Hillsdale.