"It is child's play to turn off a modern cell phone."
As if the older not-so-modern ones are hard to turn off?
My Motorola bag phone (circa 1995, I still use it) has a button marked "PWR". Push it once--no need to hold it down, and it's big enough that you don't need to use the tip of your fingernail to press it--and the phone turns off right then and there. None of this "Powering Down....." message with a 10-second wait while the phone does god-knows-what (it's not like it has hard drives it needs to sync, or something) before it finally turns itself off.
Your point is correct though - the old phones were also trivially easy to turn on or off.