Sparse tall buildings and hallway spaces are not likely at all and have no purpose at all. Floating constructions is a tempted and failed way, too much humidity, cracks and fissures, problems of sewage and networks in general (water intakes, TLCs etc) so again might sound nice on paper but a failure otherwise so very unlikely as well.
To architects: when you design something imaging it's usage BEFORE start drawing. We built for some reasons, beauty is one of them, but secondary, an added thing to something with more practical reasons; anything designed first than adapted to some purpose end up in expensive failures.
To my fellow Citizens: please when you dream your future dream it really: where and how do you really want to live? In a Goshiwong/capsule-hotel room in a dense area with some hallway and common areas in general to loitering aimlessly, maybe with a stupid smile drawn on face for the "happy-o-meter" part of the new social score? Or you dream a low density area where you can work and live in homes, with a bit of nature ALL AROUND, leaving tall buildings to specific purposes like hospitals, schools etc? Perhaps considering that single family homes can evolve, being recycled and rebuilt perhaps at generational change, while no tall building can evolve so even if it's well designed now will be a disaster in 40+ years and no one know what to do then?