Some of this has to do with people feeling qualitatively better by being in a small space that feels like it is part of a bigger space. Compare an American hotel room to a tiny Japanese hotel room. If you can't give actual space, make things transparent or cut down the size of the walls so there is openness when you stand up. It's a balance between openness and privacy.
But they also lower cube walls, or make them transparent, which goes completely against this theory.