Consider just one unsustainable sector: commercial real estate. Thanks to decades of overbuilding caused by the Federal Reserve's super-low interest rates, there is too much commercial space in the U.S.: too much retail space, too much office space, too much self-storage, etc. There are also too many new buildings on soon-to-be empty college campuses and too many hotels, etc.
The decimation of retailers has been underway for the past four years. The chart below is from 2017, and the store closures have only accelerated.

The U.S. has between 8 and 10 times more retail space than other developed economies. That suggests 50% or more of all the commercial retail space in America is superfluous.

Maybe "shareholder value" has been the greatest con in history, a PR cover story for the greatest rise in wealth and power inequality in American history.

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