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 [
as per ]https://jellyfin.org/docs/general/server/media/movies/ and letting themoviedb.org handle it all for you.
You can ignore all games from publishers on Steam. I’d recommend doing this with any publisher with anti-consumer practices.