Worth reading some of the detailed NTSB safety analysis, as part of the recommendations to the FAA:
https://www.ntsb.gov/investigations/...ts/ASR1901.pdf
I found the following about MCAS failure and AOA-related warnings to be relevant to this thread:
The NTSB reviewed sections of Boeing’s system safety analysis for stabilizer trim control that pertained to MCAS on the 737 MAX. Boeing’s analysis included a summary of the functional hazard assessment findings for the 737 MAX stabilizer trim control system. For the normal flight envelope, Boeing identified and classified two hazards associated with “uncommanded MCAS” activation as “major.” One of these hazards, applicable to the MCAS function seen in these accidents, included uncommanded MCAS operation to maximum authority. Boeing indicated that, as part of the functional hazard assessment development, pilot assessments of MCAS-related hazards were conducted in an engineering flight simulator, including the uncommanded MCAS operation (stabilizer runaway) to the MCAS maximum authority.
To perform these simulator tests, Boeing induced a stabilizer trim input that would simulate the stabilizer moving at a rate and duration consistent with the MCAS function. Using this method to induce the hazard resulted in the following: motion of the stabilizer trim wheel, increased column forces, and indication that the airplane was moving nose down. Boeing indicated to the NTSB that this evaluation was focused on the pilot response to uncommanded MCAS operation, regardless of underlying cause. Thus, the specific failure modes that could lead to uncommanded MCAS activation (such as an erroneous high AOA input to the MCAS) were not simulated as part of these functional hazard assessment validation tests. As a result, additional flight deck effects (such as IAS DISAGREE and ALT DISAGREE alerts and stick shaker activation) resulting from the same underlying failure (for example, erroneous AOA) were not simulated and were not in the stabilizer trim safety assessment report reviewed by the NTSB.