Earlier quoted context omitted.
The model size:training image ratio seems more like an implementation detail more than anything. The fact that people are writing prompts with named artists, and phrases such as "Trending on Artstation"- yeah, I'm not sure if you can just handwave that away.
In some ways it’s just a coincidence that those prompts do something. You can use names of artists that don’t exist and those work just as well, once you’ve figured out what they mean. Also, even if the model didn’t come with knowledge of an existing artist someone could fine-tune it in, and it’s possible the model can learn about your art style without seeing any of your images anyway.
Others have alluded to this, but I'll make a larger claim: human artists actually are doing very little that is original. The styles, composition, and subjects are all derivative works. That means their "essence" can be recreated without them.
Another fascinating consideration, if artists names were excised from future models, either by law or by choice, the "mirror" artists (fake) could be the ones which become famous and the humans forgotten.
AI could become more generalized or there may be millions of models, doing specific things, strung together like with APIs. Either way, if an artist or trademark owner chooses some kind of explicit blocking, from the input side, it is possible that it would be the equivalent of your keyword censored from Google's index, Google Maps, Amazon, and so on. Disney? I don't recognize that word.