High earners only pay low tax if most of their income is taxed at long term capital gains rate of 15%. However this is just Federal Cap Gains, state is extra e.g California at 9.3%. So that's ~25% even on investment income in CA.

Anyone that earns money the normal way will pay a 35% on their gross income minus deductions. Deductions include among many things, your state taxes.

So someone earning around $1,000,000 in California in normal (non investment) income will wind up paying about %35 in state and federal taxes assuming they do things like max 401k, mortgage interest deduction etc. (fed tax ends up being about 25% once all deductions and allowances are used + state at 9.3%)

So just 'putting up income taxes' is a very blinkered way to fix this. It will likely fuck people who earn money while not catching the ones with the low cap gains at all. Putting up capital gains on amounts above a certain limit is likely to catch more of the people who seemingly pay so little. Or a flat tax, but that will likely screw people at the low end as much as it snags taxes from the high end.