Music is for enjoyment. But, you may argue, music can be for making money, too. Sure, but music does not become valuable as a commodity unless it is somehow enjoyable to someone willing to buy it.

The invention of the automobile includes more than wheels, motor & fuel. The automobile also requires a system of roads. It is fair to say that music was discovered, or simply observed as in the case of song birds. So, we can say that the first musical instrument was, perhaps, the voice. But, music requires more than instruments, it also requires ears.

(Pardon a digression while I get this question out of the way. You may draw your own conclusions. :-)
If a tree falls in the forest and nobody hears it does it make a sound According to Wikipedia

If a hit song plays on a radio and nobody hears it, is it still a hit

If an artist plays an original song to a room of 30 people and everyone cheers enthusiastically,
is the song a hit

For every song played on the radio there are hundreds, perhaps thousands, of songs that the music industry does not consider worth investing in (check out Where's the Money.) From the artist's point of view, trying to create and enjoy music while also trying to make a living at it is daunting (check out Making Money....)

My point is that we can have fun discussing anything we like, but if we want to enjoy music, we want to hear it; (or, at least feel it.) AND, we are largely dependent on the music industry for sources of good music unless we create and share it ourselves.