MB gets a lot of new artists, labels and maybe other data.
I wish it would be fine to have a Notability Policy.
E.g. no artist without a release, recording or work (or other relevant relationship) or no label without releases.
There are some automatic deletes but they will not work if the entity has relationships.
Since this is well known, guys add relationships.
There are also a lot of Wikidata links added but often the Wikidata page is deleted very soon (often by not fulfilling the notability policy).
I think the policy on MB should take care of notability.
It may also be fine to have an automatic delete of deleted links (e.g. check new linked Wikidata pages a few days later).
Maybe also new editors should have less rights for new data (e.g. no direct creation of new labels/artist but only in case of adding/editing releases or respectively recordings).