**IF** human error is the real cause, then it’s not just the left seat guy who was in error.
It’s easy to get complacent when you’re on autopilot and have experienced hundreds if not thousands of hours of prior trouble-free automated flight control, and those have encouraged you to be less than fully attentive and/or situationally aware.
The folks IN the cockpit likely had SECONDS to gain control of the aircraft after the autopilot said “I completely and absolutely give up in 50 different ways”.
Sadly it appears they did NOT take the right series of initial steps in the right time frame.
Yes, I know the facts are still a long way off, but ...
pure conjecture and I’m not a pilot but I did stay at a Holiday Inn.
The tube on the outside of the plane iced over and the computer was receiving inaccurate air speed information.
The plane stalled and the pilots spent as much time fighting the computer as they did trying to recover from a stall.
Assuming they were at approximately 35,000 feet they would have had at least 4 minutes to recover from the stall before impacting the water. They should have been able to recover if the computer let them. Or perhaps they did recover and were too aggressive causing some kind of structural failure.