I have been very unhappy with the OP problem as well. A basic Windows function (that even mac

has). MS really lit a match in the dynamite shed on this one

. Solution: install the open source Windows Classic Explorer:
Welcome to Classic Shell
You will get your classic status bar back

, can hide the oversized (and frustratingly unhelpful) Details Pane, and be happy with Windows again

. It shows remaining disk size as well as the sum of the size of folder contents/selected files/folders - even in the Recycle Bin. Restores what MS tried to rob us of. I am running it on Win 7 64-bit.
They also have a classic start menu, but I am fine with the Win 7 start menu so I unchecked it during the install.
Now if they only had a donate link! (I am not affiliated with them at all).
Regards and Happy New Year.
MYD