While the results on Nvidia's website aren't too impressive, if you look at the history of animated movies [1], one can see how trivial and simplistic the art and animation was.
Having had some experience doing some research on GANs at university, I know them to be very powerful. What's very important to note is that the images generated my the model are truly "novel" i.e. completely fictitious. The images generated may be biased to some of the training data such as color and texture of the water and rocks for example, but every image is a fantasy of the model. The only way the model can generate such realistic images is because it has a very good abstract internal representation of what oceans, waves, rocks are.
Back at university, I pitched the idea to my professor of using GANs for generating "novel" images in real time while parents would read bed time stories to children. I didn't get very far. Glad to see some real progress in that direction.