This is expected behavior here since introducing the Music app. Roon requires the iTunes .XML to import playlists, since generating the .XML is a manual operating now with the new Music app, you will need to sync it manually, unfortunately I don’t have better news for you here.
Hi, i reinstalled Mojave . Catalina sucks .
Sorry for the rudeness .
As others stated here , just setup a machine for test purposes .
If its not working … take a step back .
Never update live systems .
If anybody needs a 2012 Mac Mini for testing and lives in 230V land, I have 4 of them to spare .
For free, just for shipment costs , all working , no warranty .