> Even if they had parsed it into some structure this would be the equivalent of a KeyError popping out of nowhere because the code assumed an optional key existed.
How many KeyError exceptions have brought down your whole server? It doesn't happen because whoever coded your web framework knows better and added a big try-catch around the code which handles individual requests. That way you get a 500 error on the specific request instead of a complete shutdown every time a developer made a mistake.
Crash is a feature, though. It's not like exceptions raises by itself into interpreter specifications. It's just that it so happens that Web apps ain't need no airbags that slow down businesses.
That line of reasoning is how you have systemic failures like this (or the Ariane 5 debacle). It only makes sense in the most dire of situations, like shutting down a reactor, not input validation. At most this failure should have grounded just the one affected flight rather than the entire transportation network.
How many KeyError exceptions have brought down your whole server? It doesn't happen because whoever coded your web framework knows better and added a big try-catch around the code which handles individual requests. That way you get a 500 error on the specific request instead of a complete shutdown every time a developer made a mistake.