I have one easy reason why we all organize our music alphabetically.
Because many of us are tied to that archaic creation, the album. And many of us listen to, and judge, musicians based upon that criteria. I may be an old man at 26, but when I decide I want to hear The Who I put on The Who Sell Out, or whatever album I want to hear. I don’t care that it’s most closely associated with Britney Spears and then next.
There’s some value in organizing a music library with tags to easily create playlists based upon mood. That can be helpful, if you want mixed music. But why would I organize my music in any way but alphabetically? You provide an argument, but no evidence to back it up. I want to be able to find a band/album/song easily. Anarchy belongs in the streets, not in a library or music library.
When you do your laundry do you put your clothing away by % cotton, or do you put it away by type of clothing. I’m sure it will be very useful when you’re trying to find that specific pair of pants and have to dig through 20 shirts that happen to have a similar fiber makeup.