I think Trump thought he could do Art of the Deal with people (The UniParty and Deep State) who live for power without ever producing anything in the real world. He was wrong. He has nothing they want. He has much they do not want.
When he did not fire all unelected apparatchiks at the very start - as did Clinton! - I knew we would end up more or less where we are: Swamp in charge, no Wall built, lost House majority, Impeachment a possibility.
The politicians do the ‘Art of the stabbing the people in the back and front’ just for the enjoyment they get.
See John McCain as an example.