RR_NDB, for all your asking for reasons for the pitot redundancy you surely don't think that the failure was in the pitots rather than the obvious common mode failure of the air itself, do you?
If this icing can affect a Thales probe it can also affect any other probe if conditions are "just right." So simply changing probes is more like sweeping the problem under the rug than solving it.
You're on about just one of the contributing factors that led up to the AP/AT disconnect. Yes, any one of those factors changed could have changed the outcome here. It won't change the outcome in some other cases.
Some of the things I can see for improvement (with my personal bias to "communicate") include:
- communicate not shrug when DAKAR does not answer,
- deviate around storms, know your radar (radar training),
- pseudo-airspeed (GPS derived for as long as altitude and ground speed remain "sane"),
- a variety of probes (sadly not possible as only two are qualified),
- modified pilot training (What do I do when a stall warning appears? What do I do on AP/AT disconnect?),
- reduce cockpit information overload in crisis (obviously conflicting warnings MUST be solved),
- and more.
I am sure people here can see more. And some of the above may involve solutions too expensive for an accident that for all its horrible nature is way down in the statistical noise for historical levels of air safety.
(The AirBus is a remarkably safe airplane already, possibly with 10s of billions (American) of air miles flown with this accident representing around 4000 miles of that or a one in 7.5 million accident rate based on air miles. Even if nothing substantive is done will it materially change the aircraft's safety record over its remaining life in the air?)
(Wikipedia says 789 planes. I figured 750 flying 18 hours a day 300 days a year at a piddly 400 MPH for 20 years - 32 billion miles flown. Heh, that's a bit more than the number of milliseconds in one year.)