My earlier point was that people will leave phones on, for whatever reason, and that planes are not falling out of the sky willy nilly due to these left-on phones. I'm sure that most of these phones left on are not based on 'uneducated arrogance for short term satisfaction'.
There is stuff that the airlines do that positively encourages phone use. Hell, you can use the fuckers until the cabin doors close! What kind of messed up message is that giving to passengers?
If the measure of the sense of keeping phones non-transmitting in flight is simply 'do they fall out of the sky?', then patently we should all be encouraged to keep our phones on. However, and as you've spotted, aeroplanes rarely fall out of the sky for any reason, let alone because a passenger is trying to ring aunty Nell on their Nokia.
However, there have been several occasions where large passenger aeroplanes have suffered 'navigational anomalies' (ie for a short period of time, the kit didn't know where it was), or 'instrument anomalies' (where the indications on engine or other instrumentation is varying randomly). These events have, after much testing and investigation, been put down to the probability that mobile phones in 'search' mode, amplified by the characteristics of the structure of the aeroplane and the juxtaposition of the phone to the structure and the sensors involved, have generated a signal that
could interfere with the aircraft's systems.
The consequences of this have not been, and are unlikely to be, the destruction of the aircraft. However, 'navigational anomalies' in the final phase of flight, in bad weather, when the kit is absolutely essential for a safe landing in the right place, are highly undesirable and
could be contributing factors to, say, a diversion to somewhere else with better weather, or, at worst, a botched automatic landing - with all that that implies. Equally, in the cruise, navigational or other instrument anomalies are likely to persuade me that a diversion to a suitable nearby airport is preferable to continuing, with all the cost, inconvenience and delay to you the passenger - and far greater inconvenience to the airline in investigating the 'fault' - that would be incurred.
More modern and larger aircraft are less likely to suffer these anomalies than older or smaller ones, but for consistency the same procedures are applied to all public transport aircraft, and are mandated by the various aviation authorities acting in concert. That mandate has the law behind it in the form of the Air Navigation Act.
Aircraft and IFE systems are currently being rolled out which allow the safe use of mobile phones in the air. Whether that's a good thing or not depends on your perspective, but it will be quite soon that your ears will be assaulted by the person next to you calling Aunty Nell and exclaiming, in a voice that needs no electronic aid to transmission, "Guess wot, I'm on A PLANE!!". Relish the silence while you still have it.
Incidentally, and apropos MV's tale about electro-magnetic testing of military aircraft, in the late '70s or very early '80s, I was piloting an RAF Hercules and about to take off from RAF Marham back to base at Lyneham. Next to us was a formation of two brand-new Tornado GR1s which had automatic wing sweep (not at that time fitted to the F2 version). We got a message from the tower to call 'Ascot Ops' (our bosses at RAF Upavon in Wiltshire), so we fired up one of the 1000w HF radios. As we began transmitting, I was aware of some consternated chat on the UHF ATC frequency. Turns out our transmissions were interfering with the Tornados' wing-sweep electronic gubbins and the wings were moving of their own accord! I later discovered that the EM assessment of the Tornado had been curtailed for whatever reason - though it was quickly resumed; not long afterwards I took a number of BAe and RAF engineers to the USAF EM testing establishment at Albuquerque to complete the job!
ETA: 3G phones most certainly do create the familiar 'handshake' interference, particularly when they are struggling for a signal. We hear them very frequently on the aircraft's intercom while we're in the pre-flight preparation. Usually it's our own phones...
Also, in the old days of analogue phones, it was certainly possible to use them in the air. I did, frequently! But only in good weather, and when I could see the ground.