hot take: Most people who were on the Internet in 1998-2013 has some MP3s on their computer. If 5-10% of those people have music that isn’t on streaming services, then beets has value. The ceiling on that 5-10% number is “what % of those people have so many files that it doesn’t make sense to manually fix the metadata?”.
Some attempt to document how to contribute:
With 55k lines of code as of 3 years ago, no wonder beets is so complicated: