Your examples are fair, but allow me to offer a counterpoint. Your argument seems to verge on absolutism, as in "if it's not perfect, it is worthless", which m

Your examples are fair, but allow me to offer a counterpoint. Your argument seems to verge on absolutism, as in "if it's not perfect, it is worthless", which makes me feel like it's a little dismissive of the value that musicbrainz has managed to build. I'd like to argue that most if not all data collections like this, including Discogs, Musicbrainz, web stores like iTunes or Google Music or Amazon are always going to have some data quality issues. It's the nature of the beast. I've seen data quality errors even in Apple Music and Spotify, where you'd think they have vetted data from labels directly. MB has not one scholar but thousands of enthusiasts contributing to it. Some are very methodical and provide source links with each edit (creating, as you say, traceable provenance to a reputable authority). Some are newcomers and just throw data in, and need to be educated on how to do it better. The great thing about MB is the powerful data model, and the UI that makes it possible both to fix the invalid data, and to trace the history of the edits, with links to the sources used for the changes. The other great thing is that it has, so far at least, somehow managed to elude most of the attention of vandals and trolls that plague places like Wikipedia. It feels like most if not all contributors to the site act in good faith to their best knowledge (lacking though their research skills may sometimes be), and when their submissions are lacking, they are easily improved. Finally, I do agree with your ultimate statement - none of these data sources should be taken as the sole source of authority.