Whereas it's a great theory for the press and Airbus that 3 experienced aircrew all forgot the basics of how to fly an aircraft simultaneously, it is of course horse manure. This is just another example of
Cognitive Dissonance
When two simultaneously held cognitions are inconsistent, this will produce a state of cognitive dissonance. Because the experience of dissonance is unpleasant, the person will strive to reduce it by changing their beliefs. Sewell (2006)
When the aircraft started departing from the indicated pitch and speed, the crew were forced to use their experience do determine what was really happening. When some things didn't fit that model, the model was likely changed to accommodate that. Everybody mistrusts a computer, but air instruments are supposed to remain reliable. When an air data computer is driven from air instruments and then to the AP, the symptoms of failure now become complex and less intuitive.
Pitch and thrust control will generally keep you alive, but at night, in a storm, with a cacophony of alerts and warnings going off and the AP trying to fix a problem that didn't exist, somehow the standby AI and thrust settings were not recognized as being the only control references that could be safely relied upon.
Any one of these crew could have probably executed a flawless stall recovery if they had recognized what was happening, but at the given flight level it appears the aircraft rapidly got away from them. So once again the history of aviation safety has an example of a relatively benign event - in this case the failure of the pitot heaters - conspiring with other circumstances to build a scenario that proved fatal for everyone involved.
The fact that the pitot failure was a known condition simply adds to the sorry tale of tombstone engineering practices conducted by the OEMs.