Ah, I see. Personally I think I could have taken the "give an example of a classifier" question into a deep dive of their competency (talk about how one would build that classifier, etc.) but they might get so many completely unqualified candidates that don't know those things that they need to have those sorts of hurdles before they start really evaluating you for more holistic problem solving traits.

But if you don't think they did that at all then I guess that's bad!

I generally am for the "look things up" argument, but so many people in tech take that to an extreme of "I can fully understand an entire discipline by looking at the Wikipedia page for 5 minutes".