Large parts of the floor would be illegal to hand to anyone due to lack of natural light: They are only reasonable for offices because most of the floor doesn't have full walls, or said walls are transparent. They are also in locations where you might not want to live anyway, as there's minimal commercial support around the building for the services you would need if living in a weird, limited apartment.

It's a bit like how suburban commercial areas are now in trouble because there are fewer companies interested in the big box anchors, and without them many a strip mall stops making economic sense. But there at least the anchor is just a big empty box, not an 8 or 9 digit investment.