This analysis is spot-on. I especially think you're onto something with your reference to the commons. (Edit: The generative AI movement could be a seen as a modern reincarnation of enclosure)
These guys think of a commons in a sense of ownership: if I own something, I can do whatever I want with it.
But the real historical examples of a commons are more like a mutual obligation. It's a relationship, not a delivery of inert goods. Yes, you get access to the benefits of the commons, but that comes hand-in-hand with accepting the duty to care for the commons as an ongoing entity.
That's what really irks me about all of this. They didn't "steal" something. They killed a collective organism.