The following part is true, the rest not so much.
“Bill Clinton was responsible for several very un-progressive fiscal decisions (over turning Glass Steagall, cutting welfare, etc.) but because of the tribalism of the two party system, the democrats felt like they were “winning” or something.”
Post WWII favored the Democrats simply because manufacturing was abnormally concentrated in the US. This created a bubble of high paying jobs and powerful unions, producing a middle class surge. The late seventies commenced a natual unwinding of this American worker advantage. And then on top of this inevitable realignment of manufacturing, it was corporations pushing outsourcing of production and job killing technology that undermined the old White working class jobs and standard of living, not Democrats turning their back on the rank and file.
The bottom line is that what had worked for Democrats in the 40s, 50s and 60s turned against them from the 80s onward.