That's not so obviously clear cut. Can the model produce identical output from the same simple prompt?
None of this leads to an obviously clear cut legal position wrt copyright.
If we were all honest, we'd give up the idea of copyright altogether where ML is concerned. You can't get much closer to "It's just math, man" than what it is currently.
Of course, "it's just math, man" isn't precisely a legal argument, either.