The equivalent to Plex is Jellyfin I think, Plex can be used as a media server for Kodi.

The CD wasn’t really suited to be played Mobile (though I did have a portable CD player). It should rather be compared to vinyl in that regard.

I think tapes are great because no portable audio player ever came close to the Walkman regarding its cultural impact. The fact that anyone could record tapes opened up a lot of creative options.

For properly mastered music to be enjoyed at home on a potentially expensive setup, the CD was very close to perfect.