There's a reason why MusicBrainz SQL schema looks like what it looks like, after years of careful simplification to achieve an optimum approximation of reality.
10+ years ago at Zvooq, during the golden age of music metadata and recsys startups, we tried to really solve entity resolution in the domain. I've never seen another streaming service make an honest attempt at this, even at Spotify with their 2014 acquihire of the Echo Nest. You still get Utada and Hikaru Utada as ~completely separate entities
I think MusicBrainz did a great job to find some common agreed denominator between all these styles and formats for music metadata. After setting up Funkwhale [1], I went through all my 16000 MP3s and synced those with the MusicBrainz Library, also adding new entries. It went pretty smooth and my library looks much better now. It is also really fun to listen again, when everything is structured and labeled.
(btw., yes, I bought a large percentage and, nowadays, mostly buy on bandcamp [2]).
What.cd had a very simple data model and it had the same issue as many music sites trying to fit it into a simple schema (and not a more sophisticated one like MB). The first issue that comes to mind was artist with the same name, these ended up being the same artist (Just like on Last.fm) if not split by hand by changing the artist name.
https://musicbrainz.org/doc/MusicBrainz_Database/Schema
10+ years ago at Zvooq, during the golden age of music metadata and recsys startups, we tried to really solve entity resolution in the domain. I've never seen another streaming service make an honest attempt at this, even at Spotify with their 2014 acquihire of the Echo Nest. You still get Utada and Hikaru Utada as ~completely separate entities