Without a region in which at least 2 million live and move and have their being, we are condemned either to gross congestion or the atrophy of too few people to sustain the basic elements of living.
What my notion of cyber-communities and cyber-cities does is build from the bottom up toward such a regional concept. A cyber-community of up to 10,000 persons can be built from the existing settlements and eventually replace them. These can be connected by yet-to-be invented evolutions of buses and trains - public transit. All communities will be walkable. A cluster of 10 cyber-communities would nest within a larger region containing 100 cyber-communities. A region could consist of from two to ten such nested elements.
Human governance needs to be accessable to communities that are themselves intelligible as living areas. A cyber-community is such a unit. Ten such suggest a reasonable city size.Individual communities would contain a few of the larger structures. Many presently large structures would be be scaled down to function in the cyber-communities. For example a cyber-community would have infirmaries but a hospital would exist to serve ten cyber-communities.
Because cyber communities would be global and trump distances by means of technology there is no reason why, in a nation like the United States, such communities could not be created de-novo anywhere.
Elsewhere I have suggested that interstates be the likely locations for cyber communities.
