Actually, that article is full of errors regarding painting, art history, and a lot of his criticisms of PG's take on art history are just plain wrong. Which is typical of painters. Many don't even know the chemical makeup of their pigments or which ones are dangerous and why. Many don't know about how projection was used to do a huge amount of art long before there were cameras.
The reason people use analogies for programming is it's not as common in the general population so we need something they can latch onto that they do no. Music and art are deeply embedded in everyone's knowledge, so they're easy analogies. Math isn't as deeply embedded so it's not as useful unless the person has a background in math.
Even then, I've taught people with solid math or engineering backgrounds that still struggled with programming concepts. Programming is just weird and hard to explain.