I sort of agree, but I also think you're over-reacting. Here's why:

Determine value is incredibly hard, thus many people use other attributes as a signal of value: Sometimes it's appearance, sometimes scarcity, sometimes hearsay, and rather often price. Therefore, if a product category had a price of zero, it will be considered less valuable when looking at the market as a whole.

However, that doesn't hold for every individual. For example, I still use quite a lot of Open Source software and it's free as in beer. That doesn't mean it has no value to me. If it had no value, I simply wouldn't use it.

By analogy, most music is already valueless to most people and has ever been. They wouldn't listen to it whatever the price. Nevertheless, some music will remain valuable to some people, whatever the price.