If you are under the threat of violence that won't save you.

better yet, a pass code option to show a bare user account without access to the real user data

If you are realistically in a situation where that would happen, and you would be harmed, they may just decide to kill you as you're no longer of any value.

In this case, a blank phone probably means no entry and not actually harming you. So, there's that, I guess.