"For the time being" because the terms of the cost-benefit relation shift with technology and culture. Technology shouldn't be so unruly for a society of cooperative producers. Perhaps there's something to the claim made by business and technology pundits that today's information technologies have inherent (unintended and largely unrealized) democratizing tendencies. On the other hand, if history is any guide, people will grow increasingly impatient with hierarchy, even if there are appealing technical excuses to justify it.
An acceptable, temporary middle ground might be to look for cost effective ways to prevent what appears now as a necessary technical hierarchy from becoming a very hardened, self-perpetuating, vicious social hierarchy. That would not dismantle immediately a technically-based hierarchy (it wouldn't try to do so, because the costs would outweigh the benefits), but it would blunt its rougher edges.
Julio