Sure - I can understand that. And on reflection, this typically only happens once or twice for each new moderator as they learn the ropes. Once they realize the implications they are more careful.
But figuring out how whispers works has a learning curve and this accident happens to everyone, and it is a hassle for admins to have to explain it over and over to the new moderators. if it were easy I would be happy to see the feature. But if it is not easy then I agree it is not a high priority. We have learned to live with it.