The basic fact that needs to be contended with is that the Constitution, however brilliantly it may be crafted or repaired, is a piece of paper. It has no agency to enforce or do anything else. It's always people who have to decide to do things, maybe under inspiration from this paper or another. So whether the Constitution say "Congress must impeach a President who is doing this or that" vs "may impeach", that would have 0 practical impact.

Consider that most totalitarian states have constitutions that explicitly forbid torture, discrimination, and many other forms of government suppression of people. This does little in the face of a police state bent on suppressing the people.