A nose dive maneuver (and any that are clearly anomalous and dangerous) should require simultaneous action by the co-pilot as the likelihood of a double murder-suicide would be incredibly small.
I’m wondering what happens when the M/S death rate is 100x the stall death rate; would engineering controls would be added?
In all seriousness, check out AF447. The plane crashed because the pilots were inputting different commands on the control stick and the plane picked the wrong one