With the "upgrade" to Catalina I noticed that Music (once part of iTunes) did not import anything from iTunes. I dragged a folder onto Music and the files downloaded into the app. The problem is when I launch Music only a small fraction of files are there. They still exist on the drive but I do not see them within Music. So … I drag the folder AGAIN onto Music, all the files load and show up on the app but are usually gone again next time I launch the app yet still on the drive.
Additionally, I noticed that playlists I created in iTunes did not transfer. I later found them empty in Apple TV.
All in all this is probably one of the worst system upgrades I have experienced. A few years ago there was an upgrade that destroyed several of my external drives. This has not happened with Catalina but I have experienced a large number of issues that rendered my 2017 iMac useless until the recent upgrade release. In alll honesty, I feel like I am crawling out of the wreckage and I am very sorry I did not hesitate to accept Catalina.