Of course the airline should be prosecuted, not the manufacturer. If you taxied an aircraft and crashed into the hangar or another aircraft, that would not be the manufacturer’s fault.
Those pilots apparently flew through convective clouds, iced up, then failed to correctly follow the Unreliable Speed memory drill. They then mishandled the aircraft and stalled it, then failed to follow the Stall memory drill. Having made these blunders, one of them then incorrectly held rearward stick for most of the subsequent descent into the sea.
We have since learned - if it is true - that the Captain was ill or not properly rested.
So, for sure it is the company that needs to address its training* standards and crew behaviour down-route.
*I think that during every SIM: It should be mandated that every pilot should be allowed to practice and then be checked on all the memory drills, and have to fly complex manoeuvres without the flight directors or auto-thrust. Otherwise, how can we know if we are competent and keep our skills sharp?
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