It's not clear because it's not very well-founded. There's a vague notion coming from the "alt-right" that universities are being taken over by neo-Marxist post

It's not clear because it's not very well-founded. There's a vague notion coming from the "alt-right" that universities are being taken over by neo-Marxist post-modernists. I think it's a simplistic rationalisation that some people find comforting or easy to believe somehow. The best data you can get to back is up is the fact that academics tend to be much more left-wing. But that's meaningless; academia might simply be much more appealing to someone with left wing values in the first place. Academics have always been left wing and both the hard sciences and the humanities are left wing.