I'll add that I do subscribe to Apple Match.
So, apparently Music sync to Cloud is turned on but I can't figure out where. I've looked in my iCloud account and see Photos, etc but no Music.
If I go to my iOS device Settings>Music>Sync and try to turn it off, it warns me that it will delete any Match songs.
As I said, it's not very intuitive (I think they are just trying to force me back to the Music subscription...but, I have hundred of CDs of the music that I like - ALREADY on my MacBook - so after trying Music, I realized I don't need it.