When you are very rich, you can borrow money at interest rates that are next to zero; you can also take your income in stock, rather than cash. Stock is only taxed when you sell it, and then at the lower capital gains rate, because the IRS rewards gambling and punishes work.
Put those two facts together, and you’ve got wealthy people who effectively never “earn” any taxable income — instead, they stake their assets as collateral on tax-free loans at sub-1% interest.
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