What do you consider a "fair share" that the top 1% should pay in income tax?

[Dave says]

26. 10,000 households hit the 91% bracket in 1950

I agree with all your points except the “hardly” one.

While 10,000 can be thought of as “hardly”, it is (to me) about economic justice.

https://taxfoundation.org/taxes-on-the-rich-1950s-not-high/

I am of course talking about marginal rates, “tax brackets”. Adjusted for inflation, income above $4 million is taxed at that level. We have far more people making over $4 million today than $200,000 (in 1950 dollars) then. There are far more dollars exposed now to the top bracket. Taxing them with a 90% bracket will proportionally bring in more dollars than it did in 1950.

Overall (including federal, state, and local income taxes) the top 1% pay about 6% less in taxes than they did between 1950 to 1959. For me, for economic justice, that 6% belongs in the coffers of tax collectors.

As for the idea that it is easy for the rich to avoid taxes, it isn’t easy. That’s why they pay so much to tax lawyers and accountants to help them. I’m ok with that effort. The lawyers and accountants likely end up spending more of their income on goods and services than the rich who already have everything. Value is created every time dollars change hands. Push that income down the income ladder and more wealth (for all) is created. It’s about velocity of cash flow. When stuffed in the pockets of the wealthy, that velocity slows down.

But getting back to your other good points, I’d throw a progressive wealth tax into the mix.