Everyone in the US misses the 50s, marginal tax rates were crazy high. "Oh, but people had lots of deductions and not many people actually paid the top rates" - yeah, that's exactly the point, it encouraged money to be spread around more. And a whole lot of people prospered, while government revenue was less lopsidedly concentrated too.
Get people away from paycheck-to-paycheck debt loads and you've improved a lot of lives regardless of if those people are egalitarians who will then vote for utopian policies. We know that allowing more and more consolidation ain't the move.
We have 4-5x the normalized GDP per capita compared to the 1950s.
The amount of taxes we collect isn’t the problem. Excessive government spending and inflationary pressures on things like housing is (Which, btw seems to always go up regardless of what political side you want to point fingers at)
While the economic output per person has indeed increased 4-5x, the inflation adjusted median household income has only increased by 50% (1.5x). Government spending is not the issue here.
The things you mentioned are always a problem because even the far left in America is incredibly right-wing.