Your dark scenario need not unfold at all but people must wake up. When 60-80% of the American people support and badly need the policies that can raise everyone up but the so-called representatives are going out of their way to not deliver, we no longer have a representative government and therein lies the problem. Both parties are serving their corporate masters and the establishment Dems are now the party that the GOP was a few decades ago while the GOP is just off the effing rails but neither party, with a few exceptions in the Dem party, are advocating for the will of the people. The USA used to be number 1 in the industrialized world in affording people upward mobility and now it is number 34 and that is not an accident.
The reason why the US used to be number 1 in economic mobility in the world was because most of the West was recovering from WW2. Outsourcing wasn't a thing yet, because the developing world was too primitive to do much of that. We were also the most desirable place to invest in.
Decades later, things changed as the rest of the West caught up, and the developing world was advanced enough to provide cheap labor and somewhat reliable production.
There is no path in which America can return to the economic golden days of the 50s. It is an absolute fantasy to think otherwise. If anything, the Boomers lucked out, because they happened to be born at the exact right time to experience an advanced nation at its economic peak in comparison to its competitors.
We can increase economic mobility here, but it won't come from more regulation or more taxes. It also won't come from corporate bailouts.
The Dems are going to have an interesting time reining in the social left, however. They promised to support reparations and healthcare for illegals, so good luck with funding all that.