If you’re wealth is in stock that have voting rights and you founded the company, getting rid of the stock is risky as it reduces your control over the company. In that case, if you sell you stock to lower your wealth, a bad faith actor could come in and depose you. If you’re a “good millionaire” then this could then have the effect of lowering your charitable giving potential.
Stocks are essentially people putting bets on you and your company. Most billionaires don’t just become billionaires by themselves…the public anoints them.
And I think the public should be able to rescind that if the person does more public harm than good.