I don't live, or have lived, in the US, but I consider myself a political junkie, so I'll add my two cents. I struggle to express my feelings concretely into words, so bear with me, please.
The problem with the Democrat/Republican thing, even if I nominally agree with your points about deep polarisation and lack of dialogue, is that the political spectrum of the USA is deeply to the right, when compared to Europe. Republicans are mostly corporate religious neoconservatives, Democrats are neoliberal economically, and socially liberal. There is no social democrat, let alone a socialist like Corbyn. Bernie Sanders is the only major player who you could call a social democrat (he calls himself a "democratic socialist", but his policies are social democratic). So a "middle ground" politician in the USA would be comparable to someone who is centre-right economically, like Angela Merkel or David Cameron, and with social policies that are adopted only by the most socially conservative wings of mainstream centre-right parties in Europe. That makes the Republican Party an extremely rightwing one. They are funded by billionaires (David Koch, Sheldon Adelson, etc.), who expect them to protect the interests of the rich. They have built a dark money network, and used the Senate's undemocratic make-up to install right-wing ideologues (from the Federalist Society group) on the Supreme Court and lower courts, who have struck down laws limiting billionaires from spending excessive amounts of money in elections (Citizens United v FEC), and struck down protections from voter suppression for minority populations (Shelby County v Holder). To achieve their goals of eliminating regulations on corporations, and cutting taxes for the wealthy, the Republicans ruthlessly rely on undemocratic means, voter suppression (prevalent in the South), demonisation of immigrants and deification of the military, along the occasional middle class tax cut (the 2017 tax bill cut taxes for the middle class temporarily, before raising them to above pre-2017 levels by 2024, while corporate tax cuts were permanent).
So when you call for "civil discourse" and reaching a "middle ground", that means negotiating with an undemocratic party controlled by the richest, to maybe reach a compromise that is well to the right of the political centre. And because more and more Democrats are realising this, they have started fighting as ruthlessly as the Republicans. But they will never reach the level of the Republicans, because, fundamentally, the Republican Party wants less federal government, ideally none at all (barring the military budget, because they also want to please their military-industrial complex overlords, but that's a story for another day), so they don't care if their tactics destroy public trust in the government, while Democrats believe in using government as a force for good, so they are careful to abuse its powers.
About so-called "cancel culture", to address Loco's jibe about "regressive left", I generally agree that ostracising someone because of their views is not good, unless those views are naturally repulsive. However, collectively organising boycotts and calling for someone to be fired is free speech. Right-wingers are happy to shout "free speech" and "1st amendment", but they don't like the taste of their own medicine.
And do you really think Trump will make it easier for you? His chief immigration adviser, Stephen Miller, openly wants to ban all immigration. He just doesn't have the chance to do so, thankfully.
Eliminating excessive regulations and taxes for small businesses is good. My dad is a business owner, I know the struggle. However, it must be offset by higher taxes on multibillionaires and big corporations, to prevent the quality and funding of public services from dropping, along with worker protection through higher minimum wage, and workers having a seat on the board of directors (without workers, no company can function, so a seat at the table where all the major decisions are made is only logical).
Great post. Couple of things I'd add.
In general the 'people' of America aren't really well-represented by the political parties. The Republicans and Democrats pretty much represent business interests. While, there is a big majority that would want something like 'sensible' gun laws but it's pitched as being a 50/50 divide. Likewise, there is majority support for universal healthcare but it's presented as evil socialism.
This plays out largely in the senate where each state has equal representation. Where California with a population of 40m gets the same number of senators as Wyoming with a population of 600,000. Consequence of keeping smaller states happy two-hundred years ago leads to a huge imbalance. And you can't forget that Clinton won 3 million more votes that Trump. Democrats, I think, have won the popular vote in 6 out of the last 7 Presidential elections but only won 4. On top of this the US has a real problem with voter supression and gerrymandering of electoral zones.
When you look at the polls for the upcoming elections there is a chance for a real sea change with the Democrats potentially holding the Presidency, Congress and Senate. However, Trump and I think the Republicans will go to whatever lengths it takes to prevent this. The next six months of US politics could really shape what happens globally not just domestically. Trump admires rulers like Putin and Xi because they don't have to answer to anyone. The businessman Trump plays in here, it's nothing to do with his ability to run a business, but that he's in charge and what he says goes.