This observation is incomplete. The problem is not the absence of more sensors. It's that, in order to quickly produce (and sell) the 737-MAX, it was changed so

This observation is incomplete. The problem is not the absence of more sensors. It's that, in order to quickly produce (and sell) the 737-MAX, it was changed so much that its behavior was fundamentally different than that of the 737. The MCAS system, which was dependent on those two sensors, was developed to compensate for the degree to which the plane behaved differently. And Boeing underplayed how much the performance of the new plane had changed, and hid the existence of the MCAS system from commercial plane pilots, to the point where it wasn't even in their manuals. Had Boeing behaved ethically, they would have told the FAA that the new 737 required pilot training. But that would have diminished sales and hurt Boeing's stock price. That's the managerial misbehavior that many of the commenters in this thread are remarking on. https://www.nytimes.com/2019/09/18/magazine/boeing-737-max-crashes.html https://www.nytimes.com/2019/09/18/magazine/boeing-737-max-c...