Definitely - it's important to keep in mind that from an engineering perspective, the 737 has probably already reached EOL, and Boeing has been considering to d

Definitely - it's important to keep in mind that from an engineering perspective, the 737 has probably already reached EOL, and Boeing has been considering to develop a replacement for years (Boeing Y1 - https://en.wikipedia.org/wiki/Boeing_Yellowstone_Project https://en.wikipedia.org/wiki/Boeing_Yellowstone_Project), but that was delayed until Airbus forced their hand with the A320 neo, so they decided to offer a (as it now looks) "quick & dirty" upgrade of the 737 to keep it competitive. So upgrading the flight computers was probably out of the question with the given development time.