I don’t think that their success will ever be really affected by AI, because people like their art style. Artists develop their own signature style with time, and it will be refined with time as well. And so people will follow them and pay them for their works and their career, because they want to see them grow. And they will stay loyal because they have been with them for so long. And it might encourage others to pick up the hobby as well, maybe at first imitate them as well at first, but will find their own signature style naturally due to the reality that the works of a copycat is creatively stifling.

With AI you don’t really have that. It will be hard to keep a fanbase because people can rather easily generate the content they see, so there is no real way of anyone to really stand out. And even if you factor in editing skills, those edits will be barely noticeable or stand out like a sore thumb. And if you manage to actually get good at editing, then editing AI images will most likely be just as stifling as well and working with non AI generated content might be more fulfilling.