Buildings will get so large that they are act as their own cities, creating space that can be returned to ecological use. Such buildings would be so large as to need their own rail systems.
But the problem is living spaces being separate from working spaces. I do hope that buildings like this get closely integrated into mass transportation. Not every couple work at the same place with their kids at the corporate school. If public transportation is not very intelligently integrated, the desolation of the parking lots that this beautiful building replaces will continue in the social dimension. From the presentation it seems as if this will be addressed by buses.