So having gotten way into AI art the last week (my avatar is now an AI art assisted rendering of myself, ). Whole-cloth art generation with AI is a long way from being ready to sub in for art suitable for a published RPG outside of certain narrow use cases. However AI assisted reprocessing of images and compositing of AI generated variations of images allow someone with basic digital image manipulation competency to, starting from a rough sketch, photograph, piece of ai generated art, or a composite of all these things, create an image of a quality that historically would have required a proper artist, in a matter of 3-4 hours of trial, error, fine-tuning, and touching up (occasionally much faster, if it just goes your way and it's a simple subject and composition). Not only that, but in the process you get to try out many subtle and not so subtle variations, and sometimes encounter some inspiring improvisations from the AI. Here's some heavily AI assisted art I've made in the last few days using Stable Diffusion, each starting from a photo of a person in the rough pose I was going for:
Each of the people took 3-4 hours or running Stable Diffusion on an image, getting 6-24 variant outputs, compositing together the several best outputs, doing manual touch-ups, and running it through again. The Unicorn came together in about 45 minutes with minimal work from me; the program just nailed it. The gentleman at the top started as a photo of a football player, the lady in the center was a photo of a model in a miniskirt, and the unicorn was a photo of a horse.
Now there are things I dislike about each of these images, and each could probably use another pass. And the resolution is fairly limited due to my computer's VRAM. But if a guy who's qualifications are "kind of knowing his way around a photo editing application" and "having a decent, mid-range gaming rig" is producing stuff like this about a week after learning that AI art was even a thing, I'm confident that someone with actual talent or skill, and/or someone with more AI art generation practice, on a more powerful computer could probably fulfill most art needs of the RPG industry, and most other industries.
I don't think the future is AI stealing the jobs of artists. I think the future is AI assisted artists and not-quite-artists displacing proper artists actually producing things from scratch by being able to produce output faster and, sometimes in certain ways, better. This is the industrialization of art, and like it or not it will be ubiquitous sooner than you think.