While talking about FB Execution questions around metrics / goals, is it expected for the candidate to talk about the user journey and user segmentation in detail? Or is the candidate expected to deep dive into metrics for most of the time (after outlining the Product Goal in plain text and its relevance to the FB mission?
No, you aren’t expected to talk about journey or user segmentation. Journey can sometimes be useful to help think through the key metrics that matter (i.e. what are the important steps of the funnel) but user segmentation is rarely discussed.