That's not a compelling explanation, considering that you're free to keep your head in a John Grisham potboiler (as long as it's not a Kindle edition), or remain fully asleep at takeoff and/or landing.
I think it is safe to say it's likely a combination of many things - this coupled with statistics (as mentioned before, very small % failure rate + very large flight volume = enough dead people to warrant having them turned off) seems the most plausible.
Not to mention that someone linked that it could very well be a problem with the cellular networks - if (hypothetically) you could bugger up an entire major tower with enough "hop" volume, I can see why the FAA or other organization would just want to have this as a cover-our-ass precaution, too.