That seems incorrect, given both their actual actions (including immediate and without warning discontinuation of existing visas) and rhetoric ("[T]hey're not sending their best.")

Trump administration has a very hostile rhetoric against ANY immigrants. For illegals, they are criminals, and the legal ones are stealing the Americans their jobs!

That is what I read from his campaign. Of cause, for legals, he might not take action too soon before he had enough dealing with illegal immigrants. However legal or illegal, both are not welcomed by he and his supporters, just a matter of priority.

As a non-US person I must ask, what do you mean by non-immigrant? That's presumably a specific technical meaning, because people who come to live in a country on a visa are, by definition, immigrants. Does it just mean that it is meant for temporary residence?

They haven't shown us that they aren't both yet. Legal immigrants are on edge as well.