> You might expect that if you believe in the law of supply and demand, but as we were discussing, that is not how prices are actually formed, and anyone betting based on observed supply and demand (to the extent that it is actually possible to observe them) will be beat in general by others who are betting based on current speculation, which is how prices are actually formed.
But we do see prices approach optimal. Your argument is predicated on the idea that the law of supply and demand is only a useful model if the actual price always follows observed supply and demand. But for that to ever be true, it would require speculators to have a crystal ball, otherwise there’s no reason to believe the speculated price will always match the “optimal” when the point in time being speculated about actually occurs.
The law of supply and demand tells what market systems will trend towards. But like complex control system, having a governing idea about long term trends doesn’t mean momentary perturbations don’t occur, it just helps you understand what the system will do after the perturbation.
To claim that the law of supply and demand is useless, is like claiming that Hooks Law is useless for understanding how suspension systems in cars work, because perfect springs don’t exist, and cars don’t remain stationary.
Perfect markets don’t exist, perfect information doesn’t exist, so why would anyone expect real markets to perfectly follow the law supply and demand? And clearly markets do follow the law of supply demand at the macro level, when long periods of time are considered, otherwise commodity pricing would be entirely arbitrary and wouldn’t in anyway reflect the value of the commodity to society at large.