I suppose it is the difference between being a driver on a road, or perhaps even the manufacturer of an automobile, and knowing anything about the messy business of road construction.
For one thing, everyone seems to focus just on consumer internet. But this is hardly the whole picture. Most people spend over half of their waking hours at work. To the consternation of many employers, people probably spend more hours on the internet at work than at home. And the market for business internet services is highly competitive and quite far from monopolistic. It perhaps shouldn't be surprising that a smaller number of names stand out in the consumer space -- it seems to happen with all consumer products.
Further, even the argument you posed is self-contradictory. Do you know how much a 30% market share is worth? It's worth enough that plenty of people are building to compete in that space right now.
