My employer didn't even give an excuse, the manager just said that transfering me "had never been part of the discussion", despite having been over on a two week business trip to see if I was a good fit for the office in Chicago. I didn't even need visa sponsorship, and I had already discussed that with the manager.

I belive that HR "got to" the manager and told him the company wouldn't sponsor a visa for me, so the process got shut down.

And they are right to be cautious. They will be scrutinizing H-1B and by some accounts the L visas as well. They are wanting to see if they are paying the salaries they should be paying and if the work is indeed what it was claimed to entail. There is a thread here by LouisB that talks about this and I believe gives a link.

Yeah, gone are the days of people waltzing on in with no qualifications or education on H1 visas.......

I suspect you are right. I think in practicality very little will actually change, but "Trump" will be a justification for HR to not do a bunch of things.