It is a fallacy to think that the web is the only large network that requires scale.
Goldman Sachs alone stores more data than the entire web
The Visa network has had 4 seconds of downtime in decades
Most airline systems took decades to engineer
Payment processing only deals with one type of data: money. This gives you as many shortcuts as the number of constraints it imposes.
Airline control and departure systems are probably as close to a typical modern web app as you'd get from your list.
My point is that while there certainly are engineers that have worked with high scalability issues without ever touching the web, they have also likely been solving slightly different problems.
P.S.: Other systems that require high availability but are not the web: telephony and cell communications, broadcasting and doomsday devices.
Edit: Oops, here's the link: http://www.forbes.com/global/2002/0916/038.html
Goldman Sachs told me when I was writing a proposal for them years ago that they have over a petabyte of data stored. The web is 80-200TB depending on who you ask. A single department there responsible for the program based trading would alone have an entire copy of the web (and parts of the deep web, and all of twitter, etc.) since they construct those whack trading apps that suck everything up and analyze it for signals. If there are any quants on here they could tell you about this more.
The airline system I was referring to is SABRE. Early IBM was built on their rollouts and we are talking about the 50s. V interesting story, lots of references from this page: http://en.wikipedia.org/wiki/Sabre_(computer_system)#History
(it was ~10x the web at the time)
It would be interesting to get more recent figures and compare again, because I do know that the investment banks hoard a lot of data.
In terms of just documents, they would easily store more than the web
Why would you believe that Goldman Sachs stores more data than can be reached by HTTP?! Only YouTube amounts to petabytes of data. http://beerpla.net/2008/08/14/how-to-find-out-the-number-of-...
the point is that it is frikkin big - and most investment firms now scan the entire web for signals
startups don't have a monopoly on working hard or working fast, and it is arrogant to generalize about both .NET and enterprise developers in that way since we are all in one way or anther standing on the shoulders of earlier enterprise work (where do you think what we call 'nosql' and think is new and grovvy, was first used?)
Second, arrogant really isn't fair because I certainly never gave an assessment of my own abilities or value.
Third, totally.. .NET stands on the shoulders of the same stuff the infrastructure that runs most of the internet stands on. It's just that .NET doesn't run most (or even lots and lots of) the internet.. so to suggest that the .NET development community is less likely on average to be ready to build Facebook doesn't seem like blasphemy.
That's very different from suggesting the .NET camp isn't full of awesome, hard-working developers... but really, I apologize if it comes off that way. Definitely don't mean to suggest it in the least.