There's a lot of thought that goes into things like the greebles on a spaceship, like the shape language, the values and hues, etc.

Impressionism might seem "random" like what a model would output, but the main difference is the human deciding how that "randomness" should look.

The details on a model generated art piece are meaningless to me, no one sat down and thought "the speckles here will have to be this value to ensure they don't distract from the rest of the piece."

That's more what I look at when I digest art, the small, intentional design choices of the person making it.