In my book all of these are clearly in the progressive genre.Two essentials that I love..
King Crimson - Court of the Crimson King
Yes - Close to the edge.
It doesn't get any better than these two... Oh.. Rush is a close 3rd...
Yes even invented the genre, no?
Indeed, they all have elements of psychedelica, but they have little to do with the SF scene of he mid-sixties, that was the bench-mark.