I have written this somewhere else here. it is quite simple: taxation that aligns with behavior goals and income / wealth distribution targets.

What are the behavior goals? Do you mean forcing her not to be to good of a musician, so that other musicians can compete with her or to simply limit her creative output?

Sane semilinear tax algorithm (rather than brackets where the upper most bracket only affects the lower middle class at best, the rich have successfully lobbied themselves into not being taxed) with a 100% tax wealth cap after a certain amount (let's say $10m annually).

Ofc everyone hates this idea, idk y'all think you'll be billionaires one day, or otherwise think that someone deserves to make more than $Xmn a year, in a way you're right, because nothing will change, we'll never actually tax the rich properly...so I suppose that means you win.