I think somebody should develop a standardized and open auto redaction flagging scheme for anything printed, where cameras and any software meant to share photos can offer the user to redact every sensitive field in a secure manner.

Something like a Qr code saying "this stuff in that position relative to this code is sensitive", giving the user a prompt saying "this was redacted; undo?"

With people taking pictures of their breakfast and posting it to Instagram these days... that's a great idea.