I guess my question is why does it seem like an illegal service? Not saying it isn't but it feels like non technical people will say "it knows the lyrics and can tell me them so it must contain them."

To me the technology is moving closer to mimicking human memory than just plain storage retrieval. ChatGPT gets things wrong often because that process of presenting data is not copying but generation. The output is the output so presenting anything copyright falls under the appropriate laws but until the material is actually presented some of the arguments being made feel wrong. If i can read a book and then write anything, the fact your story is in my head shouldn't be a problem. If you prompt the AI for a book...isn't that your fault by asking?