I think ML-generation is in a different class than procedural generation. Sure, technically it's procedural underneath it all, but in practice, this is a different category, and I think the products of ML might end up being more compelling than the procedurally generated game worlds you're talking about.

Take Midjourney for example - the quality, diversity, creativity of the images is subjectively (to me anyways) better than any traditional "procedural" art. When ML starts being able to put whole compelling worlds together... what is that going to be like?

Anyways, your point about infinite supply driving value to approach zero is certainly one thing we can expect.

Have you ever played Minecraft?