Why should a system provide fairness to a user who is banned? The purpose of not informing them that they are banned is to slow down their attempts to work around the ban. Shadow banning is what you do when you do not want to interact with that user ever again. They are no longer a member of your services.
This does not masquerade as providing fairness at all. It's nothing to do with fairness. It is removing that user in a way that makes it difficult for them to come back. That is all.
This does not masquerade as providing fairness at all. It's nothing to do with fairness. It is removing that user in a way that makes it difficult for them to come back. That is all.