In high school in the 60s we learned that this is a type of
regressive taxation designed to shift the burden from the wealthy to the poor.
i.e, i f I earn $40K to support my family, I spend every penny of it and pay tax on every penny spent. I have nothing to save and grow. BUT if I earn $400K to support my family and I spend (lets say) 200K living well and pay taxes at the same rate as the first guy on what I spent, I have left over $200K to invest and grow...and grow...and grow. And I can pass that on to my heirs forever because they won't have to work or pay an inheritance tax. The rich get richer, the poor get poorer!
FWIW In 1944, the top rate peaked at 94 percent on taxable income over $200,000 ($2.5 million in today's dollars)
History of Federal Income Tax Rates: 1913 – 2023