Not an engineer but reminds me of a similar situation I've seen interviewing

Sometimes we'll ask market sizing questions. We will say it's a case question, it's to see their thought process, they're supposed to ask questions, state assumptions, etc.

Occasionally we'd get a candidate that just doesn't get it. They respond "oh I'd Google that". And I'll coach them back but they just can't get past that. It's about seeing how you approach problems when you can't just Google the answer, and we use general topics that are easily accessible to do so. But the downside is yes, you can google the answer.