The other day I watched a YouTube video of ClassicsToday.com editor Dave Hurwitz about the “George Szell - Complete Columbia Album Collection” on his channel:

Spotify has an official Sony playlist for this box set with 106 CDs and 698 tracks, but not Deezer:

But as you might already know, Deezer has a free version of the playlist converter TuneMyMusic.com in your account settings:

https://www.deezer.com/account/transfer

So I could transfer almost the entire collection to my Deezer account, only four tracks are missing:

I compared a few Wagner tracks from the playlist and could hear a difference in clarity and three-dimensionality between Spotify’s lossy Ogg Vorbis audio format and Deezer’s lossless FLAC streaming. If you do this yourself, be careful to adapt the volume difference between the apps, as louder is always considered better.

Of course it would still be nice if the Deezer catalogue team could simply add this large CD box set to the catalogue (not sure if it is possible), but using TuneMyMusic.com is a good alternative if you know the playlist URL from elsewhere.