I suspect it would be a good idea if the US abolished the presidency and moved to a parliamentary system. Turns out that concentrating so much power in a single position is a bad idea.
The president has all the power that the congress and the senate gives him. Previous presidents were not given this much power. The bad guys are in the congress and the senate for not upholding the constitution.
But turns out there is no way to enforce this. If we get a president that doesn't care about any of this and is happy to ignore everyone else, there isn't actually any way to enforce the separation of duties of the three branches.