Quoting from their page:
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This is by far the largest music metadata database that is publicly available. For comparison, we have 256 million tracks, while others have 50-150 million. Our data is well-annotated: MusicBrainz has 5 million unique ISRCs, while our database has 186 million.
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If they truly are on a mission to protect world's information from disappearing, they should work with MusicBrainz to get this data on it.
Alternatively, it would be amazing, if they built a MusicBrainz like service around it.
In either case, to make the data truly useful, they'd need to solve the problem on how to match the metadata to a fingerprint used to identify the music tracks, assuming that data is not part of the metadata they collected.
> n either case, to make the data truly useful, they'd need to solve the problem on how to match the metadata to a fingerprint used to identify the music tracks
How is that a problem?
for each track in collection do extract_fingerprint
It would be reasonably trivial to set up a bot that mass-imports metadata from Spotify to MusicBrainz (note that MB rules do not allow this, community cleanup from a single user doing this with another source, years ago, is still ongoing).
The value that MusicBrainz adds is the community editor who spent a few hours going through YouTube videos and wayback machine social links to figure out that Fog (Wellington, NZ, punk/post-punk) and Fog (Auckland, NZ, Post-Punk) are different bands - even if they share a Spotify profile. The editor that hunted down and listened to 5 compilations that have mixed up a radio edit and an original mix of a track, to find out which is which, and separate them in MB and make notes. [these are made up examples]
That's not to imply that these two projects are 'competing', or that the ISRC figure comparison isn't useful and correct. But community database + scraped data is apples and oranges. And a mixed fruit bowl is wonderful.