bearfoil;
whether due to unreliable data (A/S) or a sudden onset of turbulence, that exceeded the A/P's programmed parameters
Both are possible, and I tend to agree, vice 'not using radar, or otherwise not avoiding the obvious'. I also concur with your assessment that by the time the ACARS messages were 'in process', (to use Airbus terminology) the safety of the flight was already compromised. I take as evidence for this the rapidity with which events unfolded, (essentially, 4 to 6 minutes), and the potential for crews to respond effectively (meaning, to stabilize a rapidly unfolding series of events). I have seen and know the surprise effects upon crew members of such (inadvertent) bank angles and subsequent a/p disconnects; it is
not pretty and can indeed result in disorientation.
PJ2