It was interesting to see how Apple tried to market the fact that you have to look at the phone for FaceID to work. I see that as a hassle, not a feature.
I don't think it went far enough. Consider the circumstance where an office or agent wants your phone unlocked. Your passcode is protected, your thumbprint is currently in debate, but holding your phone to your face? If that just always unlocked your phone without any sort of interaction from you? That's an uncomfortable level of privacy loss.
https://www.theatlantic.com/technology/archive/2016/05/iphon...
iOS 11 has cop mode at least.