See "Economies of Scale" [1]
To the degree that efficiency is increased with larger scale, the market will become an oligopoly or monopoly.
Most things are economies of scale: healthcare, social networks, manufacturing, network protocols.
However, even a thousandth of their scale is enough to demonstrate that decentralized scale is possible at the level where there can be economies (or diseconomies).
Google's scale was already huge even when they had merely "more than 10,000 servers" in the years prior to their IPO.
Because things are easier when devices use the same protocols as many other devices.