The engineering knowledge isn’t under NDA but there’s no way I could fill an hour long interview about the systems I work on without getting into enough specifics about our business processes to violate NDA.
If I were asked a question like this I’d wonder if I were being tested to see how loose-lipped I am with sensitive information.
I get it...I tend to think in point solutions as well, but getting stuck there is the problem and moving past that to abstract point solutions into a systems design that talks about the architecture of the solution and the 'why' behind the design choices is what gets you out of NDA-land. None of that stuff the next level up is proprietary. Specifically how it was applied in that problem domain is.
If I were asked a question like this I’d wonder if I were being tested to see how loose-lipped I am with sensitive information.