Legalities on using a camera during take off and landing

[Ancient Observer]

NZS is right
Some electronic devices do interfere with some electronic systems on board planes.
Given that CC are not expected to know which ones do interfere and which ones do not, and whether or not the interference is a safety risk, the blanket instruction to turn them all off is the only way to deal with the issues.
if you do not like it, do not fly. Take the train/boat/car. AND - do not get on the plane when I'm on it.
The End.