> Anyone with a moderately sized music collection depended entirely on iTunes to manage their library, and were hence locked in to the iPod/iTunes eco-system. There was no reasonable alternative.

Sorry, not true. I had a large music collection, and did not bother with iPod in the early days (and when I tried much later, didn't like scrolling wheel). It did not work with OGG Vorbis, nor could it have any moderate amount of storage. My DAP had 40 GB: iRiver H340. This was around 2003/2004.