I play the piano (badly). There are many other people who can play much better than I. There are simple computer programs which can play better. It doesn't stop me from enjoying it or playing it. Computers have been beating people at Chess for years yet you still see people everywhere enjoying the game. At some point computers will be better than humans at absolutely everything but it shouldn't stop you as a human from enjoying anything.
Sure, but a large part of enjoyment in creativity for many is the joy of sharing it with an audience. To the degree that people are spending their available attention on AI-generated content, they have less time and attention available to spend listening to and watching art created by humans.
