My theoretical answer is this: in an ideal world, there would be no copyright at all. This is an artificial contrivance that was once dreamed up to serve physical-copy economy, and it was rendered obsolete by the digital age. Shit would be so much easier when we got rid of this shit and everyone could share everything by default without any profit motive. (Caveat: This will not work unless literally every jurisdiction on the planet gets rid of copyright laws all at once, otherwise this is way too exploitable due to power imbalance. So I don't think this is a practical proposition. *cough* unless we all decide Anarchism is a good idea after all *cough*)

My practical answer is this: Welllllll we're kinda damned if we do and we're damned if we don't. My personal feeling is that AI creations aren't really copyrightable, and even suggesting they are copyrightable is kind of opening a huge can of worms regarding what exactly counts as "creativity" in the first place. The best we can do under current copyright regime is to regulate how the AI datasets are curated, because goodness knows the current datasets weren't exactly ethically obtained.