I am sincerely curious as to how music could be not qualitative (IE, quantitative). Is better music just more notes? Or more words? What numeric value of music would be better? Making more money, perhaps?
Or are you saying that a music's popularity, in terms of how many people listen to it, is how you determine it's value?
That is definitely an interesting way of looking at it. I can't say it's not a valid way of measuring it.
I think there really is music that is clearly better, but only subjectively. But you're right, a lot of hipsters think that there is objective quality in their particular brand of music. But I think they are just a different section of average.
