They're paving a road to hell.
You realize that the check and balances never required that different parties head each branch of government?
I'm not sure you have even a basic understanding of how the US government is organized by the US constitution.
They do in effect, because the existence of political parties means there is no reason for members of the same party to check and balance each other across different branches, as opposed to collaborating across branches to consolidate their power.
Which is exactly what's happening.
The Democratic and Republican parties are not monolithic. They don't always agree and there are plenty of differences across individuals.
Hence, the Founding Fathers never required that a different party sit in the executive and legislative functions.
This kind of hyperbole isn’t helpful when the outgoing President hands out pardons like they were coupons, nor when the President can’t remember signing EOs and is known to have limited mental faculties for the past few years, all while being shielded by his inner circle. I mean the Constitution is pretty specific about a President not fit to do their job.
If you had said “the rule of law stayed dead on Jan 20th” I might disagree but it’s at least a defensible opinion.