The highest federal bracket is 37%, the highest state bracket in the US is California at 13.3%, Medicare at 2.9% if you're self employed, NIIT caps out at 3.8% - so even earning well into seven plus figures, with punitive NIIT, only puts you at a max of 47% marginal. Social security taxes stop long before the brackets kick in.

NYC has combined local and state top marginal rates of 14.776%, to go up to 48.476%.

I call BS on marginal rates exceeding 50%

Edit: even the new 2024 California payroll tax cap lift and mental health tax on seven figure incomes put it at 49.1%. Marginal rates that high don't exist in the US. Even then that requires paying payroll taxes and NIIT on the same income, which I'm pretty sure is impossible.