It would be nice if Trump's approach to governance motivated his opponents to push for a serious reduction in executive power. Instead it seems convenient to regard him as a uniquely bad actor and simply suppose things will be better once he is out of the Oval Office. I can certainly agree that Trump should not be using executive power in this fashion, but the executive should also not have the leeway to act as such to begin with.
This.
Trump is abusing his office and the law.
And the law in question really needs to be changed.
And those who think only Trump is the problem, or who advocate abusing the same laws later, only for goals they like, are wrong.
But the latter two in no way excuse the first. Declaring a completely fake national emergency in order to steal power from Congress is a constitutional crisis, and is impeachment worthy all on its own.