Simply put, The Pitch was below cruise for nine seconds from 2:10:00.
It reached its lowest value (4.5 degrees ND) just as the a/p tripped out.
As it increased, the aircraft was still in descent.
At 2:10:07 PF input back stick, after the a/c had started to climb.
The airframe was out of phase v/v ascent/Pitch for nine seconds.
The PF inherited an airframe in phugoid oscillation.
How many times had PF been handed an a/c out of autopilot? As many as he had landings logged, most likely. His stick work is a copy of the two vids grity has posted, perfectly acceptable, when approaching to land.
His elevators were following the airframe at first, from his display.
The autopilot could not keep up with the turbulence, and tripped out. Out of this trip came airflow that sensed airmass inconsistent with the airspeed prior to its disturbance, and so the airspeeds were lost.
In two seconds, the handling pilot was given an impossible task. True to form, just as the Airbus got into hot water, it changed the "rules", and took a powder. So now, the Pilot has a very long list of things to learn, or die. Not the least of which is to acclimate to a Stick that has morphed into a goblin in ROLL, and a PUSSYCAT in PITCH. Has he trained for this?
I think NO. As someone has said here, put a single engine pilot in a twin, and pull an engine at liftoff. What are his chances? Not good.
At 2:10:00, the a/c started a phugoid. Was it speeds? No, I think airmass related. Had it been speeds, I think the engines would have been throttled, and they remained at cruise level. And if not speeds, then ICE is not a player.
For good or ill, in my opinion, this flight was out of control when the Pilot's input doubled PITCH, at 2:10:11. One can insist it is complex, and it may be, but had PF had a current Attitude display, and listened to PNF......