It's an Envelope Portfolio from the late 1980s. It looks ok to me, I don't see why an unstructured style like this wouldn't have an extra reinforcement on the bottom but I'm not familiar with the actual bag.
The color might be Putty.
I didn't think the bottom piece was all that wrong, I just hadn't seen it before, even in newer briefcases. It makes sense and matches everything else, so I'm satisfied. Thank you, Hyacinth. Have a good day!