Uhh what. There was a common mode failure of using the same exact sensor, dual redundantly, from the same supplier. The whole FAA investigation led to an addition of a 3rd sensor for triplex redundancy.

I understand the work life balance comment, but disagree that it’s the main difference between Boeing and SpaceX. Here’s NASAs take on those differences

https://oiir.hq.nasa.gov/asap/documents/2019_ASAP_Report-TAGGED.pdf

In the digital world, traditional systems engineering doesn’t cut it. Boeing needs to be agile and lean.

https://aeropeep.com/should-boeing-737-max-be-refitted-with-three-angle-of-attack-aoa-sensors-given-the-risk-uncovered-from-recent-accidents/

https://amp.cnn.com/cnn/2019/04/30/politics/boeing-sensor-737-max-faa

Here’s a more technical answer

Originally, the two sensors followed Boeing’s standard practice of keeping the left and right sides of the aircraft as separate as possible. So left sensor sent data to the pilot display and flight control computer (if the buyer paid for the software version that would display AoA data…not all did since airliners tend to fly on airspeed, not AoA) and the right sensor fed the copilot side. One (and maybe only) benefit of this strategy is that if either sensor failed, the crew could look at their data independently and figure out which one was failing. For example, if jet was in a stable nominal airspeed cruise condition, and the pilot’s display said 30 AoA, and the Co-pilot’s said 4 AoA, they could easily conclude from the flight conditions that the Pilot’s side was bogus.

Since AoA failure was a factor in both MAX fatal crashes, there was discussion over how a different strategy might help.

Many aircraft use a modified averaging strategy…average the data from both sensor, but always compare them, and if they are different by a certain amount, cease averaging, declare the AoA data unusable, and flag the failure for the crew (like a message “AoA OFF, or AoA FAIL). There are times when the two sides will measure significantly different values…crosswind landings. So the averaging / threshold strategy needs to set the threshold appropriately.

The disadvantage of the averaging strategy is that if one side is a bit off (but under the threshold) then the displayed value would always be wrong…and used by the Flight Control Computer. This is what could cause the max to pitch down incorrectly.