I believe you said you live in the Bay Area? It's easy to project what we see around us as being the mood of the entire nation, but the US is made up of a patchwork of different cultures with different cultural values. One of the moderators recommended American Nations a couple of years ago and I found it eye opening. It explains why I find more cultural kinship with Vancouver, BC than I do with most of America outside the west coast. Culturally Seattle, Portland, Vancouver, BC, and the Bay Area share more common values than any of those cities and Nashville or Dallas.
There are parts of the country that are very ready for a progressive president, but most of the country is not ready yet. The reason Kamala Harris doesn't stand a chance is because most of the country sees her as too progressive, not too little. Whether that is an accurate assessment or not, that is how most of the country sees her and people like her.
There is a political theory that I came across lately of phases of American history called the Party Systems. The first system was from the Constitution coming about to around 1824. There is debate whether the 5th system started in 1932 and ended with Reagan, or whether it is still going. I think Reagan was the start of a new system.
The party systems seem to break down near the end and a new leader comes along with new ideas and takes American politics in a new direction. When I was a kid my father used to complain that there were Democrats who hadn't had a new idea since Roosevelt and I could say the same about many Republicans today and Reagan. The legacy of the starter of a party system tends to exist long after that person is out of office.
The terms have been thrown around so much they have lost meaning. Different people would draw the lines differently. Some people would call Nancy Pelosi one of the most liberal people in the world, but she's actually fairly moderate, especially by international standards.
The founders both had personal experience from the revolution and many were very well versed in the classics. Nobody alive today has the former and only a handful of people have the latter.
I see those who call themselves conservatives and go to extremes are trying to recreate a past heyday when "we" were great. Trump's campaign slogan is right in that wheelhouse. For the American right, that's going back to a fictional version of the the 1950s. For fascist Italy of the 1920s-40s it was the new Roman Empire. For Germany it was some classical Norse fantasy perpetuated by Wagner. Erdowan in Turkey wants to bring back the Ottoman Empire and the list goes on.
The big figures of history are mostly artifacts of their time. The conditions and mood of at least a big enough faction of the public brought them to the fore. Hitler would have gotten nowhere if Germany hadn't been dealing with the chaos from the Versailles Treaty and trying to establish the Weimar Republic. The economic chaos was the worst part of it.
Trump came about in part from the real reality that white men without a college degree are less and less needed by our economy and whites in general are headed towards minority status. The right wing media in this country has stoked those issues to get those people to vote for Republicans. It was a calculated result by those in the Republican Party to advance their vision of the good principles of the conservative movement which include limited government and strong personal liberty. People like Steve Schmidt and Rick Wilson thought that was what they were bringing about helping get Republicans elected.
It was already somewhat hijacked by Republicans who just wanted to keep power and weren't really thinking very far ahead as well as the Deep South types who wanted to create their vision of the country which looks a lot like Apartheid in South Africa or the caste system in India looked like. With the Deep South leaders on top of course.
But all this stoking the flames with the right wing media teed up Donald Trump. He was the logical conclusion of all their ridiculous banter and he grabbed control of the party away from those who have been working a bait and switch on their constituents since the 1980s.
But IMO he had mortally wounded the Republican Party in the process.
That was the time of the First Party System.
First Party System - Wikipedia
I hope the Democrats will do a good job. I do think they will be fine at least at first because they have become hyper about ethics in response to GOP corruption.
Fascism is a complex subject with many definitions:
Definitions of fascism - Wikipedia
The GOP has become radically nationalistic and lives in a separate reality from the rest of the world. Whatever you want to name it, it's very dangerous IMO.
Where people draw the lines for generations is different because the groups are different based on what you're looking at. You mention the Oregon Trail generation as one dividing line. I've noticed another right around those born in 1955. I've noticed most of those born before struggle a lot with learning computers at all while those born in 1955 and later are much more likely to be able to figure out computers. Those born in 1955 were among the first people to encounter programmable calculators in the early 70s.
I've seen people divide the Boomers into at least two groups, early and late. People like Hillary Clinton who is an early Boomer think differently than late Boomers like Barack Obama. I was born in the mid-60s and by most measures I'm an early GenXer. I can relate to what you're saying. I saw a rather sharp demarcation between my year in school and the year before mine. I got along better with the older kids, but probably because I'm more like a very late Boomer than a GenXer. My parents were older (born in 1920 and 1925) and my only sibling was born in the 50s. So my home environment was more like a Boomer kid's household than a GenXer household.
I went through most of high school and college during the Reagan years and saw just how radically different youth culture was than it was when my sister was the same age. She was in college at the end of the Vietnam War era. My sister found college culture way too liberal for her tastes (my family were Eisenhower Republicans) and I found the campus environment of the 80s way too conservative.
There has not been a Gen X president, and it's possible there never will be one, but much of the more extremist political leadership are early Xers, born before 1974 as you pointed out. Paul Ryan is the perfect example of this group. He has wanted to completely revamp the taxing and budget since he joined Congress.