I would say that there shouldn't be any calls on a plane while in-flight because you never know what someone is calling for. It can lead to a bad situation like 9/11 or any form of terrorism.
Oh please ! Imagine trying to read or sleep while the yo-yo next to you or across the aisle is yammering incessantly at the top of his lungs. It would be like a screaming baby kicking the back of your seat, ALL flight and EVERY flight.
Besides ... the cellular system is designed to provide coverage on the ground, not in the air. I think every call you made from an airliner would drop in a minute ar two.
There's no right or wrong answer to a "should" question. My humble OPINION is: Please, not until Satan's inferno freezes over !
