Maybe not, but last time I looked obstruction of justice/abuse of power/perjury/extortion/ illegal payoffs/conspiracy/money laundering/etc. were still grounds for impeachment or criminal acts. Of course like "collusion" this is only a "possible" scenario.
Nixon was impeached on three counts: obstruction of justice, abuse of power, and contempt of Congress.
Clinton was impeached on two counts: perjury and obstruction of justice.
My bet is that Trump should be good for at least 4 or 5.
Except of course Trump has not done any of that and is not good for any of them. Because you dislike someone it does not mean they are a criminal. Because you think they ought not be President it does not suddenly make their Presidency invalid, nor corrupt, illegal, immoral or incompetent. Because you disagree with their decisions it does not mean their decisions are bad decisions.