... unless you plan to use the backups.
Then you have to have another service that tracks entities to delete when a backup it's restored... and back that up separately.
There's little to ponder, that's why I mentioned "entities" rather than "user data." Use unique keys to reference the data rather than sensitive identifiers. The nontrivial part is storing your backup of entities to be deleted in a way that doesn't get destroyed at the same time as the event that forces you to revert to a backup. This now requires a separate storage, backup, and retrieval mechanism to maintain compliance.
