Even for humans there was a transition period, and not a sudden explosion of new expression. Naturalist gave way to impressionism, which gave rise to expression

Even for humans there was a transition period, and not a sudden explosion of new expression. Naturalist gave way to impressionism, which gave rise to expressionism, and eventually then came abstract works. There's a clear, gradual change in style between them all. I don't see why you couldn't have an AI do the same, by training it towards a particular aberration in output until that became something it understood well.