On the Fact that, While, Yes, the Top Tax Rate In the 1950s Was 91%, the Effective Rate Was Only 16.9% (the Fact that There Were Many More Loopholes Back Then) - https://taxfoundation.org/taxes-on-the-rich-1950s-not-high/

So, no, the rich WEREN'T shouldering a heavier load back then (at least not on the federal level). That is just one more bullshit leftist talking-point.......Back to the drawing-board, fellas'.