It will be interesting to see how the second half of Trump’s first term goes, then how he reacts to reelection. That is what will tell us if the USA will survive as an almost republic or become the “Modern Authoritarian” state you are projecting.

I say almost republic because, in my opinion, we are already well on the path to oligarchy. With the same subset of people standing for election and the choices between ‘parties’ being mostly illusionary. The 2018 election was slightly better, but one election does not break the pattern of the last 50 years. It would need to last for several election cycles and move down into the state level offices as well as a few congresspeople with fewer ties to the power elite.