It may be hard to get effective tax rates for high earners above 40%, but it would be eminently feasible to get them back up to 40%, where they stood before Bush and now Trump went off and reduced effective tax rates for high earners so much.

I just mailed the feds my owed taxes for 2017; my high earner effective federal tax rate is ridiculously low (lower, because of the cut off for social security at ~120k, than significantly less well paid people).

I didn’t ask for these tax cuts, and they’re certainly not enhancing my propensity to work, they’re just going to allow me to retire earlier.

But if your point is that income taxes aren’t an awesome way to raise revenue, I’m with you. Land-value-taxes would be almost impossible to avoid, and would have the salutory effect of improving efficiency in dense urban areas.