Hard to take credit for that as the "one", but I did work on the site as a community manager near its launch. The idea (which wasn't mine) was that in a world where digital downloads existed, there would be no one store that would have them all in one place. People were likely going to need to go to multiple places to get their music, and mp3.com would act as a registry for that content, pointing you in the right direction. If you didn't see what was coming it wasn't a terrible idea.

What we didn't know then in 2003-2004, was that Apple ended up eating the entire industry (at the time) and everyone just bought an iPod and called it a day. MP3.com rightly fell apart shortly after.

Weirdly enough, that assumed model and need now exists now that content has fractured again, this time with video. Which service is streaming that movie I want to watch? We're getting to the point where we need those registries as much as we need "caniuse" for browser comparability.

Should that directory concept have been attempted on a very important domain like mp3.com, itself having fallen apart earlier in the Internet bust? Probably not, but hindsight is easy looking back. Back then domains were more important.

Anyways, just answering to some trivia for you. I didn't have much to do with that site's origins.