My point is that water is NOT worth 50 dollars a bottle and monster cables are NOT worth 100-150 dollars just because they work.
Blue Jean and Monoprice cables are 5-10 dollars and they work too. The water from my faucet cost pennies and it “works”.
Maybe I’m missing your point.
You are correct: things are not worth a certain price because they work or someone merely says they a worth a certain amount. They are worth the price because someone voluntarily paid the asked amount. It is why your services, whatever you do for a living, are worth what you are paid. This is basic price theory.