r/StableDiffusion has a thread asking users what the one image their inscrutable gacha machine created for them they value the most is, and the answers are even more cringe than you expect.
It's really fascinating to me that this is what people make when the barrier to artistic creation disappears. It reminds me of some Youtuber books - they're written by people with no literary skill or experience, but they produce them because they've gotten popular enough that the books are a profitable endeavor regardless of quality. Until you read a Youtuber book you don't consciously realize what is necessary to write a book, because usually, mostly, only people who have that ineffable something do write novels. And here: you don't realize what is needed to actually create art and not just images, until you see people with no artistic literacy or skill produce what they think of as art.
Visual art and literature are windows to the soul, and normally only a certain type of person goes through the effort to open that window for us. Here, and in Youtuber books, you can see inside a completely different type of person. And their soul looks like waifus and cowboys.
People have been making boring, soulless art by hand forever too though. Hollow pet portraits and reddit-favorite photorealistic copies of celebrity photos for example. You're right that stable diffusion has removed a barrier to entry but they're just joining the glut of skillful but completely uncreative human 'artists' already out there in the world.
because usually, mostly, only people who have that ineffable something do write novels
People have always been writing terrible fiction. Trawl the depths of AO3 and fanfiction.net, look at the great mound of rejected novels by aspiring authors. Artistic mediocrity is a part of the human condition the same as artistic excellence.
For the most part, the "ineffable something" required to write a good book is years of practice, an editor and the barrier to entry that is convincing a publisher to take you on.
This is exactly what bothers me about these people and for me it's especially exemplified by the one person who posted the astronaut lady with the dogs.