Income inequality isn't an issue, wealth inequality is.

I find it perfectly fine to earn 8 time as much as my artist best friend does as long as we are in a market-based system. What bothers me is that I do not pay enough taxes, and could pay even less by declaring my donations.

If you were actually bothered by not paying enough taxes, you could just pay more. You can literally just go and donate to US Treasury.

No, what actually bothers you is that others don’t pay enough taxes.

Well yes, since others not paying enough taxes is part of the tax system being unfair, someone who actually cares about fairness would be bothered by it and them personally paying more doesn't fix that. Do you not care about fairness? "You could pay more yourself" has always been more of a snide low-effort attempt to shut down conversation than to engage in it. Please try to do (and be) better.

I strongly suspect that blue states are even more unequal measured by wealth than by income.