It's not the same principle. Large language models aren't 'inspired' to write new works. Software can't be inspired. It follows instructions. Even though large language models might feel like somebody is talking back to you and giving you new information, it's just code following instructions designed to predict output based on the input provided and the data supplied. There's no inspiration to be had, and to attribute inspiration to language models is a huge mischaracterization of what's happening under the hood. Can a language model, without being told what to do, actually use any of the data it was fed to create something? No. Every single large language model requires some sort of input from a user to act as a seed before any sort of response can begin.

This is why it's so stupid to call this shit AI, because people start thinking it's actual intelligence. Really, It's just a fancy illusion.

They purchased their books to get inspiration from, the original author gets paid, and the author consented to selling it. That's the difference.

Also the LLM can post entire snippets or chapters of books, which of course you'll take at face value even if it hallucinates and makes the author look like a worse author then they are.