We have no idea what is going to lead to useful innovations. The invention of the loom led directly to digital computers. Dyes (e.g. for art) led to antibiotics. Many people at NASA have credited “Star Trek” for starting their interest in space research.
Since we can’t predict what’s going to lead to utility, we should encourage people — and you should encourage yourself — to throw themselves at whatever excites them, as long as it doesn’t cause any major sort of harm.
If someone says to me he loves gardening more than anything else in the world, I’m not going to tell him to do something more useful. I’m going to hand him a spade and some seeds. If someone loves fixing cars, I want him to fix cars. If someone loves math, I want him working on equations.
Artists are important because they are people working hard on projects. Any project may or may not pay off in terms of lasting social utility. But if an artist is passionate about his work, he contributes to the pool of things that might surprise us, that might change the world.