While a lone actor might decide to end it all, there's some difficulty in persuading a larger group to go with the plan.
But there is the door and a distinct lack of tools in back to get through it. The Ethiopian pilot was unmolested during his unauthorised diversion.
Methinks there's going to be openings for jumpseaters who can both land the plane if necessary and take care of those with ideas to divert the aircraft.
Cue wails from the beancounters.