FS, the only way I can see them going to idle is they got a false overspeed warning because they climbed 3,000 ft with blocked pitot tubes which would give an overspeed warning with static pressure reducing in the climb. The 32 year old in the right seat, PF, had less than 3,000 hrs and 800 in type, probably 798 hrs monitoring the autopilot so he probably didn't stand much of a chance of hand flying it at night with no airspeed in moderate turbulence. The full up control in a stall is an Airbus thing I guess. Nobody else does that. Apparently the computer will protect you in normal law but they went to alternate law so from what I hear you are not stall protected.
Magic airplanes like Airbus take the pilot out of the loop and make them monitors and eventually they will lose their basic flying skills if they ever had them. This pilot was probably for the first time in his life hand flying an Airbus 330 in unfavorable conditions he couldn't handle.