Is it reasonable to say "X is no longer with us, we'll figure out their responsibilities with hiring a replacement, dividing areas of ownership, etc" shortly af

Is it reasonable to say "X is no longer with us, we'll figure out their responsibilities with hiring a replacement, dividing areas of ownership, etc" shortly after they depart (for any reason)? Or should the team have to put two and two together after realizing they aren't coming back? I feel like the latter is too common.