Causes and explanations
IanW: Actually they did mention the turbulence and told the rear crew that the pax should be strapped in. However, it is always like that flying through the ITCZ. The CVR and DFDR showed the LOC was almost certainly due to lack of experience/practice in limited panel manual flight at altitude with unreliable speed indications when in Alternate Law.
Yes yes but a passenger advisory is routine and not a notable comment of concern between pilots. Subsequent focusing on inadequate pilot experience/practice is too often an expediency by event reconstructors with competing agendas, and as an explanation misleads from or ignores possible airline system (et al) inadequacy and the other workload increases you mention which are all cumulative inside a time crunch. You are suggesting that 100 or 1000 other airliners, crews, instrumentation, and identical conditions (which we don't really know) would result in 99 or 999 flight completions with only AF447 failing because of the pilot inadequacy. My point regards the other 99, or 9999. Most accidents wouldn't occur if the aircraft remained completely intact and there was adequate time, altitude, and information to figure things out. AF447, and perhaps MH370 may not have had either. So were those two outcomes singular or more systemic in nature? If the latter, we should all be interested in understanding the situation as much as is possible and promoting necessary changes to prevent repetition. If in the future major loss of flight instrumentation with the most up to date systems were to occur again in the same weather situations, would it again be the pilots fault?