Seems pointless to learn to make singular highly detailed visual art pieces? Maybe. Maybe it always was pointless.

But most visual art is not just single pictures in a vacuum. Say you want to make a game with 2d still-art, or say a comic. You will need dozens or hundreds of images and they will have to be tied together by a common design — characters and style that look similar in the different images, and most of all you have to have a story to back it up. This is not something AIs can do well, not for a long while, but a human artist now may do significantly better than before with help of "dumb AI", such as the featured Krita plugin.

Finally, most artists don't think like you. It's not "pointless" to do something that can be technically repeated by other humans or AI. You do art because you want to express yourself.