Well, suffice it to say that I was really disappointed to learn that VBO seems to work pretty much the same way

This is just an "ask" for the Veeam people... would you please consider a special "archive only" license that is significantly cheaper that we can assign to deleted users who will no longer continue to be backed-up but we want to keep their data around for years, just in case we need to go looking for something? It seems crazy to have to pay for a full license (and our current solution is no different in this regard) forever just to keep archived data around for users you're no longer backing up... and even crazier to have to take that data OUT of the backup to somewhere else just to keep it (what we do today) because we can't afford to license every user who's ever been backed up, even after they are long gone.
Anyway, I hope someone from Veeam sees this and considers such an alternative license for deleted users.