I think the focus on rich people is misguided. You would get way more tax money by properly taxing corporations than you would by taxing billionaires. The personal income of even top level billionaires is still peanuts compared to corporate profits, which can be hundreds of billions per year. I don't care if Musk of Bezos has a personal wealth of hundreds of billions, that money doesn't exist, it's the hypothetical market value of their stock holdings. But major corporations do actually have hundreds of billions of actual liquid income every year, so to me that's fair game for taxing. If Walmart profits $150 billion in a year, then sure, go to town and heavily tax that, because that is actual money and not just value.