I don't see why having a broad knowledge of a wide range of music is morally superior to having a detailed knowledge of a single genre. Actually, a lot of people I know who enjoy a wide range of music don't really listen to it. Again, is it better to enjoy a lot of music at a fairly superficial level, or to listen properly to a narrower range?

The truth is that none of it matters, because it's entirely a matter for the individual. Some people like music, some don't. Personally, I'm not greatly interested in the visual arts, which would no doubt horrify some art enthusiasts. People are different - thank god. Get over it.