Why do you think we make music? To entertain others? To make profits? To find the meaning of life? To express emotions? Or to impress a certain someone? Darwin found the last one to be true. From studying birds, he concluded that their songs are used to attract the opposite sex during courtship, and proposed the same for humans.
I can see some truth in it. The main reason guys join bands is because women a guy who plays the guitar and writes love songs. Or as Joeffrey Miller puts it, Jimi Hendrix’s extensive musical career did him no survival favors (he died at 27). But he had sexual liaisons with “hundreds of groupies” and fathered AT LEAST three children! Can you imagine what that number could have been before birth control came along?