No one paid that. Back then there were all sorts of deductions that are now gone and many ways to shield income, that are also gone now.
If you truly had a 90% tax in the top 5% why would they even go to work anymore? You can only tax the wealthy to a certain point but it is mythical that you can get enough extra tax monies out of that group to fund anything else.
I remember reading a book about Abbott and Costello and one of them fell behind on their taxes and the rates at their income were so high that they could never catch up.
The IRS just took their property.
Happened frequently