Utter nonsense. You can't convert between a wealth tax and an income tax in any manner as simple as this, unless the wealth tax and the income tax were implemented in a simplistic way unlike any actual proposal. Most obviously, there is no such thing as "the" income tax rate, because different people pay different rates; those rates depend most obviously on the amount of income but also on various kinds of accounting gimmicks that allow wealthy people to pay less. Similarly, no one is proposing a flat wealth tax that would tax 1% of everyone's wealth.

The "example" discussing paying income tax on your $5 of return on your capital is similar nonsense. You don't pay anything on that gain unless it's income, which it isn't unless it's realized. So (assuming the various parameters of a wealth tax meant this mythical $100 person would indeed pay a wealth tax), the comparison is between zero income tax and some nonzero amount of wealth tax.

> None of them would speak of adding a "mere 20%" to the income tax rate, even though that's mathematically the same thing.

Plenty of politicians (e.g., Bernie Sanders, AOC) have pointed out that the top income tax rate during the 1950s was over 90%, and have suggested raising rates back or near to that level, which would be well more than a 20% increase in the income tax rate.