>> lots of stuff are full of current communication without classifications due to urgent needs <<
Not only that:
You never want to give the enemy free access to your unclassified traffic, because even the unclassified stuff will have clues to help the enemy decrypt your classified material. Cryptanalysts have known this truth at least since World War One, maybe much earlier.
(And somebody please correct me if I’m wrong, but I would have thought all government employees who handle national security related traffic are briefed on this principle.)
Makes total sense to me.
Obviously Hillary wanted to hide probably communications and the possible fact that she could have been still collection Foundation money and doing business at a time when she should have avoided all contact.