(Tedious disclaimer: my opinion only, not speaking for anybody else. I'm an SRE at Google. My team is oncall for this service and I know exactly what happened here; I probably can't answer most questions you might have.)

> Perhaps your architecture wouldn't "compile" if the network traffic will go the wrong place, or if a rate limit is above the capacity something is expected to handle, or if the change would impact too many servers at once.

So in the first instance, I tend to like this sort of idea. However: we are already substantially ahead of the sort of things that you're thinking of.

Full static simulation of a system as complicated as all the components involved here is... well, I can sort of see how it could be done, but it would be a herculean effort; I don't think it would ever be good enough to catch cases like this the first time they happen. There are systems where this sort of thing can be done, but all the ones I can think of are much smaller in scope.