Remember that you're able to export your Google Play Music data[1] via https://takeout.google.com

At least there's a silver lining...

[1] "A list of the tracks, playlists, radio stations, uploads, and purchases in your Google Play Music library" Key to me was my playlists, including my "Thumbs Up" playlist, which as others have noted is polluted by "Liked" music videos on Youtube in the migration