Welllll...first, the article's subject is global, not just the US. Second, the article definitely says "the billionaire minimum income tax proposed in the U.S.

Welllll...first, the article's subject is global, not just the US. Second, the article definitely says "the billionaire minimum income tax proposed in the U.S. by President Joe Biden, which targets individuals with more than $100 million in wealth...would subject the entire pre-tax return on wealth for ultra-high-net-worth Americans to a minimum individual tax rate of 25%, irrespective of whether the return comes from dividends, realized capital gains or unrealized gains". So within the US perhaps it's more reasonable to talk about people with $100M rather than $1B and laugh about the name not exactly matching the number. I don't have the exact total wealth number for that threshold, but I do have the wealth of the top 0.1% in the US, whose minimum net worth is now about $50M (extrapolate 2 years from https://fred.stlouisfed.org/series/WFRBLTP1311 https://fred.stlouisfed.org/series/WFRBLTP1311), which is close enough to $100M for me, at a total of $20.7T (https://fred.stlouisfed.org/series/WFRBLTP1246 https://fred.stlouisfed.org/series/WFRBLTP1246). Third, 2% is given as a minimum starting point. Even at 5% the money would still be increasing in the market faster than that.