Yes, but the ultra wealthy rarely are subject to taxes. They have no income. Their wealth is tied up in stocks, and they rarely sell the stocks therefore nearly never opening themselves to capital gains taxes.

They then borrow against the stocks for spending money. When they want more money, the refinance and get a bigger loan. The loan is only paid off by their estate after they die. The bank is happy to accommodate, because they’re willing to play the long game.

If you tax loans as income, you’d be screwing over the middle class who need mortgages to get ahead.