For a fully-legal alternative of metadata archiving, I suggest the iTunes EPF (Enterprise Partner Feed). https://performance-partners.apple.com/epf

The best metadata I've found, though, is the MySpace Dragon Hoard: https://archive.org/details/myspace_dragon_hoard_2010

That included the artist location, allowing me to tag songs based on their country. I then created playlists such as "NERAS" Non-English Rock Artist Sample, where the one most popular song for a particular artist was chosen, and only when the country of origin was not English-speaking, and the genre was Rock. I like listening to music while working, but English lyrics distract me because I understand what they're saying.

After discovering music via the MySpace archive, I've since purchased 73 songs from 35 artists that I'd never heard of before digging into the data. I rebuilt my playlist on Spotify, but got greyed out tracks, and YouTube Music, but got "unavailable video". So I still prefer purchasing tracks via the iTunes Music Store, Qobuz, Bandcamp, and 7digital.

Other data sources such as the MP3.com rescue barge, PureVolume archive, and Anna's Spotify archive lack the country-of-origin metadata, so are of less interest to me. It may be possible to use an LLM to guess the language of each track title, but someone else will have to do that.

Meanwhile, if you're interested in the genre-by-country MySpace data, or have questions about the iTunes EPF, feel free to reach out and we can discuss your research.