unions

The myth is that the numbers represent an objective value of a human. That is false. Supply and demand aren't a myth. They aren't the only way wages are determined, sure. But try to hire an accredited dentist for minimum wage, you can't because there aren't enough of them. That is a supply constraint that increases the prices dentists can charge.

That's not objective and not even a free market, a good amount of the price is because we have decided a certain group of people set the standard for what constitutes an accredited dentist and they decided on including X amount of schooling that costs a certain amount of money etc. But it is a supply constraint that raises the cost to hire a dentist, there is a supply and demand component in there.

It can lead to morally bad results and be something that needs to be fixed (via, for example, the minimum wage I mentioned or...naming and shaming as you imply to be the fix) while not being a myth. Supply and demand exist.