People dismiss AI art because they (correctly) see that it requires zero skill to make compared to actual art, and it has all the novelty of a block of Velveeta.

I look at art because I find it pretty, not because someone toiled over it for hours on end. Sure, I respect the artist who made it and think their effort commendable, certainly worth a sum of money, but if something is made such that the art of the craft requires less skill and time surely that is a good thing?

Novelty of the tool doesn’t matter. What’s new changes daily, and the point of a tool is not to be new but to be useful.
If you mean the art itself that is generated being samey or problematic in that sense of non-uniqueness, I disagree wholeheartedly. You can do a lot with learning models, and the sameness people perceive is from inexperienced novices dipping their hands in and flooding the ecosystem with beginner works, in much the same way DeviantArt was once flooded with drawings on the level of stick figures and box people.

If AI is no more a tool than Photoshop, go and make something in GIMP, or photoshop, or any of the dozens of drawing/art programs, from scratch. I’ll wait.

A hammer is a tool, and so is an electric jackhammer. You don’t tell a construction worker to go use a hammer when an electric jackhammer gets the job done far better and far more efficiently, and not everyone is suited to using a hammer just as not everyone is suited to using an electric jackhammer. They also have different purposes, but certainly the electric jackhammer did replace some of the uses the hammer once had, but it doesn’t make the hammer obsolete. I view learning models that generate art in the same manner as an electric jackhammer. Useful and powerful, but ultimately lacking in refinement and the work will certainly need other tools to finish the job.

This phrase of yours just doesn’t mean much. I don’t see how making something in GIMP proves anything for anyone?