It seems that the thing to do is to avoid the situation in the first place, as much as possible. The big weakness is a) presidential democracies tend to fall into dictatorship because of the power split between executive and legislature, and b) winner take all elections with extreme gerrymandering and affirmative action for conservative viewpoints/senators.
If anything were to come from this, a new constitution should be written where we have a multiparty parliamentary system, with agencies reporting directly to a prime minister from the legislature and the president basically having no real power.
But that's neither here nor there, given that Musk is tearing out the copper wire and the Trump administration has turned off the security system.
Seems as if the biggest issue is that the Constitution was never designed with the idea of political parties. The existence of the parties, and party loyalty, completely destroys the idea of 'separation of powers', and 'checks and balances', as the other branches just see their first loyalty as being to their Party leader, in the form of the President. Hence Congress is quietly acquiescing to losing its powers to Musk (and the Supremes are a wholly-owned subsidiary of Trump).