ktcanuck
The 737 has an Elevator Feel Computer whose purpose is to increase elevator control force as airspeed increases. The control forces are applied hydraulically and are separate from Speed Trim System whose function is to maintain control force neutral.
Is there a simple reason why the EFC could not have been provided with an AoA proportional input so that this existing system could compensate for the control force reversal?
That question was comprehensively answered a few pages back in this thread. The elevator feel computer does not have enough hydraulic power to generate the feedback forces for certification:
Boeing 737 Max Software Fixes Due to Lion Air Crash Delayed
2. There is not enough column / elevator feel system adjustment range to provide the compensation that would be needed. This is particularly true at high Mach / speed where the nominal setting for the feel system is rather high to begin with. There is not enough range left in the system from there to max pressure to sufficiently offset the Cm-alpha characteristic that must be addressed to meet the FARs.