

This is only true in the abstract. Yes, you are technically correct. Money only has value because a large enough group of people agree that it does.
But money is a shared token that describes the value of someone’s time and effort which can be exchanged for goods and services. It’s a common thing that can be bartered that everyone will accept. It’s an incredibly useful thing for a society to have.
This is also correct, but a different problem.
If there isnt enough money moving in circulation, it typically means that people are saving it for hardship rather than spending, which is in turn a sure sign of a poor economy.
The rich assholes at the top have been able to basically trust that smarter people will handle policies to prevent a major depression. Anyone that was old enough to remember the last one is dead now. Anyone that lives quarter to quarter doesn’t care about market conditions 90 years ago.