The ultimate reference point is whether the person watching the screen at the scanner can see everything or not. If most of the time laptops are transparent eno

The ultimate reference point is whether the person watching the screen at the scanner can see everything or not. If most of the time laptops are transparent enough then why bother asking people to remove them. On the other hand, if routinely they can't properly scan it and have to deal with delay, they will instruct people to take it out of the bag. In the end it still is security theatre so it doesn't have to make sense as long as it looks convincing enough.