I have a folder of MP3s, some of which date back to 1999, just a few years after the format was popularised. Most of them have utterly terrible names (think RIDEONAM.MP3). I think at this point they might even survive the heat death of the universe. And they’ll still be terribly-organised.
Picard is literally the only Jellyfin related tool I use that isn’t fully automated, because somehow the automated versions I could find were doing things like renaming files on a 60% confidence of the filename and I had to nuke and re download my library.
So instead I open Picard, click 6 whole buttons, and my entire library/new files are renamed, tagged, and sorted 100% accurately.