[lwb]

In my experience, CS is useful when software engineering breaks down. Many foundational abstractions in modern high level languages and frameworks are leaky. This leads to pathological behavior under stress (extreme scale, extreme performance, groundbreaking tech, unusual requirements). CS is also a big help when you're exploring new technical areas that frameworks haven't been developed for yet.

You know that person who you always go to when your program malfunctions? Or the high level engineer at your company who also seems to know how to diagnose a site incident or other strange software problem? What about the technical founder who leads a startup to do something new and extraordinary? Or how about the person who wrote your framework/language of choice? These are people who understand CS fundamentals, irrespective of whether they have a formal CS degree.