The biggest shift in my perception of the world, as I have decided to go "you know what, I'll bet there's a reason things are so stupid," is changing my attitude from "things are stupid" to "why are things so stupid." It's extremely bad for democracy that the leadership of the United States since 2016 has been older than the leadership of the Soviet Union in 1984. That's not a consequence of Mitch McConnell bathing in the blood of virgins, though, it's a consequence of the repeal of the Fairness Doctrine, a consequence of Citizens United and a consequence of the Permanent Apportionment Act. LIkewise, it's extremely bad for democracy that the principle method for political action has become the executive order. But ever since Newt Gingrich determined that the Republican Party would never again act in a bipartisan manner, it's the only real game in town. The fundamental problem, as I see it, is American democracy depends on a bunch of customs that one party has decided no longer apply to them so for 60 years, they've been attempting to pen-test the system into fascism. And for those 60 years, schools have been painting unicorns and rainbows and eliding bullshit like the Electoral College, Reconstruction and the Dred Scott decision. Americans have grown up thinking our government is this highly-polished, refined mechanism that rewards excellence and truth, rather than an archaic and outdated parliamentary nightmare with massive in-born advantages for oligarchy. And it doesn't matter to one side, because oligarchy is their whole goal... but the other side sees one punch that might not be according to Marquess of Queensbury rule and goes "that's it, I'm officially too cynical to participate in democracy and anyone who disagrees is a patsy." It fundamentally comes down to loyalty: one side demands that it be earned, the other side can bank on it through anything. It's not even a Republican-vs.-Democrat thing: the Kennedys had no problems with racism and prejudice but LBJ figured there were more Black votes than Southern votes so he cut the Democratic Party off at the roots. It could have gone the other way. If LBJ had been happy to stick with the old guard, Henry Cabot Lodge might have won in '64 rather than the guy who moved to Arizona so the racists had a place to live. But since it's "earn my loyalty" vs. "it's gonna take a lot to lose my loyalty" Republicans became the party of racism in about half an electoral cycle.
Some argue that the actual issue is the creation of the national security state, which created (effectively mandated) a disconnect between overt governance and secret control. For example note that some of the "bullshit" you cite did not prove an impediment to progress made prior to '64. In fact, one could argue that this focus on the political theatre is somewhat irrational given the implicit acknowledgement that the parties are disconnected from quaint notions of "American democracy". It is reasonable to challenge that with the reality of actual political conflict in the socio-political arena. As for this cynic, I see the partisan jostling as internal dynamics of an elite that compete for available social, economic, and (petty) political advantages and resources, (ab)using demographic characteristics to marshall support. tldr: I think the game of baseball perfectly captures the architecture of the american system. (hint: site sections can also be informative..)