"cause" and "contributing factors"
This accident/crash will be one that lives in the books for a long time - many lessons-learned. And the "cause" will not be a simple pilot error or airplane problem.
Without posting 1,000 words, I can not believe that a modern FBW system does not employ a "standby gains" feature that uses air data from 2 seconds ago when the air data system becomes "suspect" by HAL or the humans in the cockpit. Hell, you could even provide a switch/button to revert to "standby gains" if you, the human, thought something was awry.
"HAL, I think we just froze up the pitot tubes, and remember that incident a few months ago?"
"Yeah, Gums, let's use some generic air data quantities while we figure this out"., and "don't worry about overspeed warnings and such while we work the problem, Gums, we ain't gonna die in ten seconds if you just hold current power and attitude"
That is not what happened, folks.
I am not convinced that a feature of one of the "laws" commanded an AoA or pitch that was not commanded by the pilot. After that, well, the pilot could have made things worse.
I am not convinced that aircrew training emphasizes the "don't just do something, just sit there", take a second or two and sort things out. In my little jet, we had less than a second to "do something", but it was the nature of the mission and what the jet was designed to do. The big heavies don't/can't move at 20 or 30 degrees per second in roll or pitch, but mine did. Those heavies have fairly benign aero characteristics, and with full control inputs you can't come close to the rates and such I dealt with.
IMHO, human factors will play a large role in the ultimate findings. Some will be training deficiencies, and some will be related to conflicting "warnings" and having a crew trying to figure out what "protections" they had versus simply flying a decently-designed jet with a basic control law to hang their hat on.