I think the most salient point the artists make in the article is that the process of ideating and iterating on art is just as valuable, if not moreso, than the end result. You can get a good looking image from an AI generator but miss out on the ideas and discoveries you would otherwise make by actually working on that art.

I think it's also unfortunate how the advocates for AI replacing artists in gamedev clearly think of art as a chore or a barrier to launch rather than being the whole point of what they're making. If games are art, then it stands to reason the.. art.. that goes into it is just as important as anything else. A game isn't defined just by the logic of the main loop.