Definitely agree with you, there's no need to waste resources on protecting against threats that would never target you - like attempting to capture your face from CCTV and spending real money and resources to get a mask and then stealing your device... etc like you noted.

The author does have face unlock listed as "Advanced" priority. The wording is a bit weird but I take it to mean, only someone who has "very advanced" security concerns would need to follow that recommendation.

If I were going to recommend this to a friend/family member I would just tell them to stick to the basic priority items and not worry about the higher pieces.