Page faults illustrate the idea of the memory hierarchy, which is one of the most important architectures in computer science. Programmers who don't understand the memory hierarchy write slow code. You also can never do "massively parallel systems run, or how distributed databases handle consistency, or high volume scaling, or NLP or any of the other areas of CS that are far more interesting that page faults" without virtual memory, paging, and page faults.
You're confusing what's important to you with what's actually important.
"Programmers who don't understand the memory hierarchy write slow code" is just nonsense.
Most programmers today use languages where they aren't even aware of, or able to manipulate in any way how and when memory is managed. And this trend will continue as the hardware their programs run on are increasingly virtualized.
Let's face it, virtual memory is a done deal, its now fundamental until we find computer hardware architectures that don't ever have address spaces that exceed the physically addressable memory. With virtualized kernels, possibly its a better solution to boot operating systems that have no concept of constained memory resources, and let the virtualizer do the paging.
