I just started properly tagging new music at some point and now my library is largely tagged correctly.

For tagging I use kid3, great KDE application for that.

I also sort my music into a folder layout like this to know where I got it from and potentially upgrade the quality.

MusicRaw
  - Artist1
    - Bandcamp
      - Album1
    - Tidal
      - Album2
      - Album3
    - Youtube
      - ytrip album
  - Artist2
    - Album1 (not moved to a separate source)
    - Tidal
      - Album2
      - Album3
    - ytrip album

I then have a script to loudness-normalize (come fight me) all music and write it to another subfolder.
A second script takes those normalized files and symlinks them into a structure like this:

Music
  - Artist1
      - Album1
      - Album2
      - Album3
      - ytrip album
  - Artist2
      - Album1
      - Album2
      - ytrip album

I tried switching to Picard, but for somewhat obvious reasons it doesn’t support my insane structure.