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.
Just another person recommending Musicbrainz Picard.
I had about 600 sketchy music files. I had started using Kodi and I wanted my music library to look nice. So I cleaned up all the art and metatags. It was a bit of an undertaking. I actually added a few of my albums to their database. I’m happy with the result. MBP is a really cool project.