Pragmatically, is that really any different with a passcode? Someone might not be able to physically force an unlock like with biometrics by moving the relevant body part over, but there’s certainly nothing stopping someone from forcing you to unlock your phone if you had a passcode through by duress. Most thieves would have certainly wised up enough to force you to remove your passcode before leaving, or they’d watch you unlock your phone, and figured out the passcode that way.
I rather doubt that, if in that kind of situation, there would be many who would resist. Your phone is not worth your life for most.
Personally, if I wasn’t doing anything sensitive, like travelling through some countries (like Australia/the US) or going to a protest, I’d probably keep it on. The convenience makes up for it for the most part.
And normalising it is a good thing all-round. You want privacy to be used for trivial, unimportant things, not for it to be seen as something that only most secret vital things need, and thus something most don’t.
People would be more likely to use it that way.