Perhaps I'm a Luddite, or just in the dissonance phase toward enlightenment, but at the moment I don't want to invest in AI fiction. A big part of the experience for me is understanding the author's mind, not just the story being told
Also, I guess I missed the brunt of your question, though the answer is similar. Most voice works for most characters. There’s only so many ways to say something, but occassionally you have to adjust the sentence or re-prompt the whole thing (the LLM has a tendency to see the best in characters).
And unless reading is your day job or only hobby, that's a massive, massive corpus of interesting text. (In just one genre! There are more genres!) So on an absolute scale, there is so much fiction to read with more-than-surface-level meaning that I personally just don't understand why anyone would have the least interest in reading AI slop.
(I also don't have any real interest in most Kindle Unlimited works, probably for similar reasons. Though I am quite certain there are diamonds there, I've just not had particularly much time for/good luck at finding them.)
Also, you say you don’t understand why anyone would be interested in the AI slop. But from the article we learn that one is indistinguishable from the other (apparently even to the one professional author that tried)
AI content is really exposing how people fall into a group that does go further than the surface text into deeper layers of context/subtext, and a group that doesn't.