Example of why you should not use FaceID to unlock your phone, this time from Norway: in 2022, a 28yo man filmed a uniformed police officer assault his two 26yo friends. The officer took his phone, turned it towards him to unlock it and deleted the video. https://www.vg.no/nyheter/innenriks/i/8J7A5w/politivolden-i-kongsberg-dette-vet-vi
Hmm, I don't use phone assistants AT ALL, but this seems like a good case for having it on only so you can shout the phrase "Hey Siri/Google, Lock my phone." which would put it into a password/pin only state.