So scarcity was added artificially: Even though the network scales indefinitely, there's a designed-in "choke point" of congestion which can impact performance.

That choke point is called the CVC -- the Connectivity Virtual Circuit.

That's what NBNco sells to their customers, the ISPs. And its pricing is levied by the megabit, and it's the most expensive terrestrial network link available for sale anywhere in the world.