There's is a distinction between a professional skill like programming and an artistic skill like painting, which could perhaps be expressed through demand levels and commoditization.

Programming is easier to commoditize than painting. Painting ceased being a professional skill in relatively high demand upon the advent of the camera. The individuality of the painter became even more important during impressionism.

Most 9 year olds don't know about chiaroscuro in the same way most 9 year old programmers don't know about compiler theory.

I think at the undergraduate level a lot of what they teach won't get you hired if you know it but will get you fired if it turns out you don't.

Hmm, good point. Painting is, likewise, a field where it's easy to try new things and figure out on your own whether they work or not.