Everybody can have ideas, even people that aren't writers. A writer is a good at the translation from idea to paper, which is what LLMs are uniquely suited to assist.

I have already used LLMs to publish my first book. Specifically, I used sudowrite + chatGPT. LLMs are a true equalizer in writing. Correcting grammar, improving and rephrasing wording, and even helping to brainstorm and organize.