system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: With the presence of Airplane Mode, why do air stewards still insist that we turn off our mobile phones?

With the presence of Airplane Mode, why do air stewards still insist that we turn off our mobile phones? From what I understand, Airplane Mode totally cuts off your contacts with the outside world, so that it will not interfere with radio communications should you be on an airplane.
gpt
It is far easier to have one single rule to enforce than to check every phone and other electronic device to see if it's in that mode. If they see it they ask you to switch it off.

Imagine the flight delays if every device required an attendant to make sure it was in a safe mode.