Hello,
On a public Discourse instance, a user recently requested deletion of their user account, to which a moderator replied by using Discourse’s anonymization feature.
However, I quickly noticed that the newly assigned user id was usable in the advanced search form to look for all past messages of that poster. It is quite easy for such posts to contain pieces of data that can help identify the user and link their online activities with the “anonymized” account to their physical existence (for example a surname, an age, the mention of the place they live in…).
This creates a problem because it does not fulfill those posters’ request for protecting their privacy rights. They may even think their request was fulfilled while information will actually be left around and very easy to find out by others. Also, perhaps they were a minor when using that account, which creates additional problems.
While I am not a lawyer, this is most certainly not compliant with the law of at least some European countries - including, I think, France which I am of citizen of (for French-speaking people reading this, here is a link to our official data privacy protection agency’s dedicated page: Le droit à l’effacement : supprimer vos données en ligne | CNIL) . It is generally understood that deleting user data really means deletion of any kind of data that might help identify the user (doesn’t need to be a complete official name or an unambiguous identifier : any mention of personal characteristics, however imprecise, is enough).
Givens that you probably don’t want admins and moderators to go around in all past posting history of a user requesting anonymization, and manually blank out any potentially personal information in those posts’ contents, it seems to me the only reasonable solution is to physically delete all posts by that person, and any quoting thereof in subsequent posts.
Also, if there is a concern that this might disrupt past discussions, perhaps you want to give users and moderators two options: shallow anonymization (current behavior) and full deletion (as proposed above).
PS: I am not giving any links to the original Discourse instance, because it would only risk publicizing someone who asked to be forgotten about. Of course, I can send them in private to Discourse maintainers.