at one point Taxes in the US were 70-90%.
did the people ever leave ? NO
did the people ever leave ? NO
That figure is highly misleading to cite by itself because the high tax rate also came with a bunch of loopholes and exemptions. That's why despite the drop in the headline rate of 70-90% or whatever, the actual tax take as % of GDP has remained remarkably steady in the past 7 decades.
So it's not like it was actually a tax on the wealthiest, more a targeted tool to apply state power.
For example GWB "lived" in texas the whole time he worked in washington.