We have often critiqued the misperception of the decline of the us and/or modern civilization in relation to the decline of the Roman republic, empire. But in another way the comparison is inevitable.
The problem is precisely what is happening here: a telescoped version of decline as ideological grounds to dispense with a republic and move into an authoritarian system under the Caesar meme. It took six centuries for a Roman republic to turn into a system of emperors. The US analog doesn’t work.
Still, American democracy has become corrupted in record time, a mere two centuries from 1800 relative to our eonic model. But it doesn’t follow that the analog with Rome really works.
The better analogy is with the case of Athens whose democracy failed within two or so centuries from Solon (in the discussion of divides and transitions): we see the uncanny accuracy of eonic analog in that case.
Perhaps all these views work in their own way. But the decline of the Roman system is a misleading analogy. The US system should potentially have had a far longer endurance yet seems to have lost its coherence prematurely.