MusicBrainz has linked to Wikipedia for many years and we now have links to Wikidata as well. Wikidata, however, acts as a central repository for Wikipedia links, so it does not make sense for MusicBrainz to maintain its own separate set of Wikipedia links, especially since Wikipedia URLs are not very stable (because of page moves and deletions) and require a lot of maintenance. Most of our data with Wikipedia links is now also linked to Wikidata, so we plan to start removing Wikipedia links where we have a Wikidata link which has the same Wikipedia link.
What this means for downstream data users:
If you use Wikipedia links, we will provide Wikidata links but you will need to fetch the Wikipedia links you want from Wikidata separately. Wikidata has information on ways to access their data at https://www.wikidata.org/wiki/Wikidata:Data_access
We plan to start removing the links after the schema change this month, starting with the less common languages and entity types. It will take a while to work through the existing links, so we don’t expect to start removing English links from artists until after the Autumn schema change.
We recognise that some people may have code which depends on these links – if you’re using these links and the above sounds problematic, please let us know how you’re using the data (which languages and entity types) and how much time you would need to support Wikidata.