There are memes about 90% tax rate in the 50’s all over social media.
Yeah when loopholes were abundant and those rates were never paid.
On paper, yeah, there was once an excessively high maximum tax rate, but.....because of exemptions and deductions and tax shelters, nobody paid it.
Anyone who thinks Joe Kennedy gave away 90% of his income is nuts.
In fact, the alternative minimum tax was devised during the mid-1960s precisely because there were a lot of very wealthy people who escaped paying any income taxes at all.....even when the maximum tax rate was 90%.
In Macroeconomics, many years ago, I was told that no one ever really paid that much, because there were plenty of loophole sin the tax laws.