"Yeah, but computers can't be creative!" is the last line of denial for humans who don't want to face their impending obsolescence in a field. People said the same thing about chess engines, right before chess engines defeated human beings at the game conclusively, and forever. A creative brain is a million monkeys with typewriters, plus a subjective critic judging their work. Coming up with random shit and then discriminating among the results is what creative people do. If you think "creativity" is some magical human phenomenon that can't be learned by a sufficiently complicated artificial neural net, then you either don't get creativity or you don't get neural nets. Will a computer produce the next Rembrandt? Maybe not. But the average human painter isn't the next Rembrandt: they're a schmo with a bit of mechanical talent, practicing their craft.

The reason human painting will survive is very simple: because 1) people value human-made objects independent of those objects' objective qualities, and because 2) paintings exist outside the digital world, and there is no robot sufficiently dexterous to match the skill of a painter in applying paint to a canvas. That being said, as this technology matures, lots of currently employed digital artists will no longer be needed.