Trump was not the beginning of the decline, only the terminal symptom.

Terminal? We don't know if worse is yet to come.

Yeah I think Reagan's reforms of the antitrust laws, and the subsequent fall of the Soviet union are probably some of the first dominoes toward the new gilded age.

The lack of competition from the Soviets is probably one of the bigger systemic causes. The cold war in no small part a war for hearts and minds in the democratic world. It was existentially important that the west believed in America, both the US itself and its allies. As long as the Soviets were around as existence proof for an alternate world order, the US needed at least visibly have its shit in order.

If today's clown fiesta had unfolded 50 years ago, well comrade, сегодня мы все говорили бы по-русски.