Setting aside the usual arguments on the anti- and pro-AI art debate and the nature of creativity itself, perhaps the negative reaction that the Redditor encountered is part of a sea change in opinion among many people that think corporate AI platforms are exploitive and extractive in nature because their datasets rely on copyrighted material without the original artists’ permission. And that’s without getting into AI’s negative drag on the environment.
IMO I’d call “AI Artists” a type of Art Director, since they themselves don’t make the art but instead direct and dictate what exactly they want, and if the result is different they tweak their wording to direct the art into a different direction
Art Directing, whether for a human or a machine or otherwise, is still a skill itself and still has to be learned to get good results, but it’s distinctly different from making the art yourself so I wouldn’t call them “Artists” outright