That is more a reflection of what a lot of Mormons do. Every Mormon kid takes piano lessons, etc. So BYU sees a LOT of kids who choose the arts for their extra-curricular participation.
I don't think BYU requires you to be in the arts. For some kids, they have zero talent there.
BYU is looking for a well-rounded kid, not just a book worm. Service, leadership, arts, sports, etc. all fall into those categories.
My son sounds like Frankenstein when he sings and would be a terrible actor. Music is not his thing and he draws worse than I do, which is really bad.
His extracurricular strengths will fall in other extracurricular things.