A weird one - I noticed today that I have absolutely loads of songs missing from my music library. These were songs I had moved to the music library from my CDs.
I think an iOS upgrade shouldn't directly impact your music library. However, syncing or backup issues during the upgrade might lead to missing content. Check your iCloud Music Library settings and backups for potential solutions.
The previous update for me was a mare. My face ID had issue too. And I didn't know about my missing music, and wouldn't have known either had my family and I been not playing though my music library in alphabetical order on a 7 hour road trip. My daughter realised we got to N and hadn't heard Material Girl!
I'm going to head home next week and resync music with my Mac. Hopefully it'll all still be there.
I have had a similar issue, where everything I'd uploaded from CDs that hadn't matched had become damaged. It was all still present on the Mac. Reuploading has fixed everything!
I have had a similar issue, where everything I'd uploaded from CDs that hadn't matched had become damaged. It was all still present on the Mac. Reuploading has fixed everything!