Especially straight, conservative, Christian (or Jewish). Even LGB conservatives can be racist according to the left. Only leftist whites are immune from the “racist” label because they’re “down with the struggle” of the woke minority classes.
I’ve seen several stories about that. Some colleges even have entire sections of the schools that are off limits to white students. A lot of these racist “professors” are also advocating for violence against white conservative students and other conservatives. Especially in the big blue cities.