Public tax policy that either provides plentiful loopholes or high enough tax rates where billionaires/millionaires can (and are highly incentivized to) shift their money and use tax saving schemes are what's really evil.

If people spent time focusing on increasing government tax revenue from the rich rather than increasing tax rates on the rich - which just pushes more and more wealthy people to stash their money in tax shelters (see Ireland) rather than investing it at home - they'd actually succeed in improving the inequality situation. And most importantly boost the economy and create more middle income jobs (by keeping money as job-generating capital instead of sitting dormant in off-shore shelters).

Instead of expecting humans to stop acting out of self-interest, how about:

a) Creating incentives for businesses and the wealthy to not move money elsewhere by having competitive tax rates. The simple fact is having them pay something rather than further incentiving them to pay nothing would massively increase revenues without increasing rates.

b) Massively simplify the tax system to close the myriad of loopholes that allow these wealthy people to continue operating locally while shifting all tax liability elsewhere. Make it obvious exactly how much each person owes their governments at the end of each year.

Creating a tax policy that's grounded in the reality of human behaviour (you can call it evil if you wish) rather than idealistic fallacies of how people should act is the real solution here.... Assuming this whole thing Zuckerberg is creating is partially a form of tax sheltering in the first place.