I didn't use it, but it looks to me like one of the main draws of foobar2000 was library/metadata management. I've only ever used directories in the filesystem as a "library," and have used many players over the years (mainly moc, which I love, but which doesn't bring anything especially valuable to the table--I mainly just like the UI and out-of-box key commands).

Thus, to me, as an outsider, this whole conversation feels a bit like a cautionary tale about software/vendor lock-in.