I don't think it would be bad for equity in any way. It might actually be good instead actually.

First, the general public would have more disposable income if we shift more of the tax burden on the ultra rich.

Second, people like Elon Musk won't be able to give themselves massive bonuses that are essentially paid by diluting common stock.

Also, with regard to the U.S., the U.S. could wipe out its national debt with a one-time wealth tax, and also pass a balanced budget const. amendment so it never ends up deep in debt again.

Lastly, perverse and extremely greed-based exploitative businesses might become less common, since there aren't ultra fat executive paychecks. Although it might still happen if a large group of people are able to make a somewhat high salary off such schemes.