Seth Godin is not dumb

But I think he's missing an obvious answer here ...

If it’s so dangerous to have your ipod on during takeoff and landing, how come you’re allowed to have it with you on the plane at all? Does all the scolding actually increase safety? How?

You turn off your ipod so if the plane breaks on takeoff you can hear the instructions from the flight crew telling you how to get out before you burn up.  Accidents near the ground happen really, really fast: there may not be time for the pilot to say "welp, we're going to crash" twice.