That was my experience also. I had a very smart coworker, a scientist, who was libertarian, very anti-police and everything. Then Trump came along and he went full fascist. It was very disturbing, and I haven’t trusted libertarians since.

Note: I’m using libertarian as shorthand for libertarian capitalist, which is mostly how it’s used in the US, though, as noted in another comment, there are other kinds of libertarians, like libertarian socialists.