Personally and without empiric evidence, I would opine that a self-sustainable community is not inherently scalable: The human race did well with between (total guess) 50 and 100 people, having enough diversity for some to partially specialize (hunter, thatcher, miller, various other ancient surnames), but being flexible enough to cover or support others in times of crisis; and also the communal ability to establish tribal codes of conduct ("social contract") so that being a dick to someone was being a dick to everyone.
Announcing a (relatively) new, massive community without nods or counterarguments to anthropology seems... reckless.