I have my media library from 20 years ago: it is embedded in my music files using standardised tagging formats. Any in-software 'media-library' I have used in that time has simply been a cache of and search interface for this metadata. Similarly some video files support tags and there are some standards for external metadata storage that can live next to the files I believe.
I highly doubt the music file metadata shown in the video only exists in an opaque internal representation within VLC.
I don't have my "media libraries" from 20 years ago.
As soon as a tool tries to move my files into an internal representatation I cannot control, I delete the tool.