I wish we lived in a world where everyone was financially stable and able to live a good quality life #UnelashValues Unfortunately many of the economical, social, and political structures are dominated by the 1%. When you're that wealthy, the amount of power you have over other people's lives- whether direct or indirect) is unhinged and places you into a mythologized, god-like figure. I don't think any singular person should have that kind of control over an individual or the masses, and honestly don't think billionaires should exist.
While I don't think you should cap someone's earnings, setting up systems that encourage financial equity from the beginning are what we need- aka systems that don't allow people to get so unfathomably rich. We could implement a taxing scale with an exponentially harsher gradient to increase the taxes for the those who make more money while still keeping taxes low for those who make less. This means we're all contributing, just in a caliber that is properly customized to our earnings so nobody becomes extremely wealthy. At a certain profit margin (i.e. when you're making more money than necessary), and you're taxed more than for just regular tax things (like paying for roads, garbage collection, etc.), the remainder could be donate to an organization or charity or something. However, where those 'donations' go would not be decided by the person being taxed so there aren't any sneaky tax break happening and the 'donations' are being used as intended.