I love Jellyfin. I did think these recommendations were a bit funny however since they were so off.
Maybe the recommendations need to also look at the movies mpaa rating? Like something PG shouldn’t be recommended after watching an R and especially not vice versa.
I guess it becomes complex quickly if you want to add other rating systems to the mix.
Yes, modifying the value is going to break the mappings (see https://github.com/jellyfin/jellyfin/blob/master/Emby.Server.Implementations/Localization/Ratings/us.csv). Anywho, I think we’ve discovered the root of your problem. How you choose to rectify it I leave to you! Personally, I’d recommend suffixing your filenames with
[tmdbid-123456]as per https://jellyfin.org/docs/general/server/media/movies/ and letting themoviedb.org handle it all for you.