Many, if not most people want to have value to others. Including introverts. We want to behave in a prosocial manner within an embedded social context. Art itself was borne out of social contexts, especially music and storytelling. Most of us gain untold fulfilment from creating art that is valuable to others, i.e. art that people like.
I can speak to this myself: I have little motivation to create anything outside of a social context. When I create something exclusively for myself, it feels hollow. When the social context is there, I come alive. It brings me deep fulfilment to bring someone joy with art. Of course, I have to also like the art myself, otherwise it's just excessively sacrificial.
If you're individualistic enough to gain fulfilment from only creating for yourself, then all the power to you. But I'm tired of this being expressed as the only valid way to do things, especially since many people will be less fulfilled with this mindset.