Most of the issues with the database are old sins from Emby. With 10.11 the Jellyfin team finally managed to clean up that mess so they can move forward with a clean implementation. Their blog post on moving to EFCore [1] and version 10.11 release post [2] have more details.

[1] https://jellyfin.org/posts/efcore-refactoring [2] https://jellyfin.org/posts/jellyfin-release-10.11.0/