Copies are not rivalrous, but the underlying creativity absolutely is. If I pay someone to draw a picture, that's labor, and they've got a finite number of hours to sell. Except it's also very inconvenient to pay for creative works this way: drawings and artists are not fungible with one another. More importantly, quality and desirability of the work is incredibly variable. The buyer of the art is bearing the risk of the art being bad.

What copyright lets you do[1] is offload that risk onto a publisher[0]. Instead of having to pay to commission every piece of art, a publisher can do that, and then sell the now-monopolized copies of whatever art turns out to actually be valuable.

A lot of hay was made during the Piracy Wars over filesharing tools breaking this bargain. A bunch of data hoarders with an interest in sharing media made it possible to just get the shit for free. This created a social dynamic where artists were annoyed about it, but publishers were Fucking Pissed. You could even measure how publisher-brained an artist got by how angry they were over Napster[2].

AI generated art also breaks this bargain, by making creative labor nearly non-rivalrous. The only cost is electricity and GPUs. This has created nearly the opposite reaction: artists are pissed while publishers don't care, because AI is to publishers like tort reform is to insurance companies. A publisher that gets art for free doesn't care if everyone else has it, because they have the payola dividend: they can push whatever slop they want onto the market and the market will eat it because they're big and powerful.

> This concept exists to prevent violent conflict over non-shareables and to prevent the tragedy of the commons

The copyright maximalists would argue that free reuse of creative works is a tragedy of the commons. I certainly remember hearing that phrase bandied about a lot during the Piracy Wars.

It's also important to note that "tragedy of the commons" is not a natural law, but a specific framing that is used to justify antisocial ends. The communal ownership so decried worked perfectly well in England for hundreds of years until the ruling classes found it inconvenient and abolished it. The kind of ecological collapse the tragedy attempts to invoke did not happen because there were already communal means of preventing overuse of the land. In fact, an emissions market is probably closer to communal management than enclosure.

Also none of this changes the underlying logic that AI companies are trying to enclose the intellectual commons, and that their business model relies on being able to replace human brains with machine intelligence they can rent out by the megatoken.

[0] Individuals who self-publish included.

[1] To be clear, copyright was created as a censorship regime, it just happens to be useful for other things.

[2] In Lars Ulrich's defense, they weren't just angry that Metallica songs were on Napster, they were specifically angry that Napster had their latest album before it was in stores.