They kind of do belong to everyone. The technology and majority of training corpus is available to essentially everyone.

The training and inference infra are owned and operated, but I can't see an argument that any machine that processes public domain (or stolen, if you prefer) info should be available to everyone for free.

But those training and inference costs will go to zero. Think about your cell phone today versus $1m+ supercomputers in the 1980's.

We're living in a transitory blip where capitalists and gold rushers are getting rich arbitraging the cost of processing against the non-cost of corpus. We can argue about morals (it doesn't bother me much) but it is a narrow window and it will be remembered the way Compuserve is: a precursor to the actual revolution, worth a footnote.

Sure, that's what I mean by where to draw the line. An artist taking inspiration from others is not obliged to give up the work to the public.

Sidenote: It may be tricky/impossible in the future to uphold intellectual property laws. If anyone is able (for instance) to prompt-create all their software, a software patent is worthless.