I have degrees from MIT and the University of London, and I'm reasonably familiar with the student body and faculty of BU, Columbia, and the University of Cambridge.

when a lot of them graduated, they became conservative over time after they started working

I'unno about that. Research shows pretty consistently that the bulk of people's political ideology is formed on the basis of the political events that define your late teens and early 20's. And even if so -- I work in academia, so I know a solid deal of these people past their working age.

I don't think I personally know a single person with a STEM degree (advanced or not) that isn't to the left of Clinton.