How many people write anything? This kind of reductive reasoning would basically leave everyone in the world writing software that can fit nicely in a UML model generator.

It's entirely reasonable to ask if complexity is worth it on every level. Many of the greatest successes of internet protocols have come through making things as simple and modular as possible. This doesn't mean SPDY is terrible necessarily, but "no one ever needs to work with it" is a clearly wrong answer to a criticism that it's overly complex.

I guess my point is that as projects mature, there are usually fewer serious options on the market, and those options do more, and so it makes sense to capture a lot of the complexity inherent in the problem within those few pieces of software rather than force all users of that software (which are numerous) to deal with it.

Perhaps there are simpler solutions to the problem, but if they make things slower for end-users, that's inconveniencing millions to save effort for dozens, which is not a particularly good trade-off.