Maybe that works for pure entertainment.
I buy a lot of books, including a lot of nonfiction. I care quite a bit about the author. There's a lot of garbage out there with just flat wrong information. One of the few things you have to go on is an author's reputation.
Which, if you're making that up, becomes a garbage signal, and something approaching fraud. So for now at least, any outfit that publishes something that's supposed to be informative that's demonstrated to be "genai" derived means they've utterly lost my trust, and I won't be buying from them anymore.
There's also an ancillary issue I've never heard a good answer to. If you are publishing "genai" output, why would I pay you for it? I'll just ask GPT4 myself and not pay your cut.
If the answer is, "because we larded it up with all the signals that make it look like a human wrote it", well, see above about fraud.