Interestingly, git itself is a counterexample to your very point. It's written in reasonably tight code and without major runtime dependencies to run fast on a single system with a simple filesystem backing. And depending on who you ask and what their tastes are, it does maybe 80% of the job that all these giant web sites are being asked to do internally, without any rigging or support beyond a remote ssh account.

So "we" haven't collectively failed, just some of us.