This is something I was thinking about when I learned that Cory Doctorow is an adamant user of Ollama, an open source LLM (whatever that means), to do spelling and grammar checking on his writing.
If I were a professional writer with an established voice, I wouldn't touch anything based on an LLM for fear that it would subtly erase that voice. So slowly you wouldn't even notice, your writing will be barely distinguishable from anyone else's.