Re: Criminal Negligence and/or Corporate Malfeasance? Those are a Rock and a Hard Place
"with a commercial aircraft there should be no actual reason for not giving it the best possible stability and ease of control"
When I finished my apprenticeship at BAe in Bristol in 1979 I worked in the Avionics department. There were two research projects active: Relaxed Stability; and Gust Load Alleviation. The former investigated reducing the size of the tail plane, thus reducing stability, but regaining stability via a control system. The latter adjusting control surfaces to reduce thermal gust load on the wings, using a control system, allowing for a thinner wing skin. Both control systems would allow for a lighter, and therefore more efficient aircraft.
The reasons for these changes are obvious. The competitive pressures between aircraft manufacturers is huge, and the flying public expect / have become accustomed to, cheap air travel. I wouldn't say that this kind of design is defective - but the control systems must be expertly scrutinised and employ majority voting.
As others have pointed out, it's possible that where there are multiple sensors if one sensor fails, they might all fail. In this case the failure must be detectable and ... safe. Perhaps for this particular aircraft more effort should have been taken to design a more robust AoA sensor.