MCAS can be relatively easily fixed. Add sensor redundancy, fault logic, improve emergency warning system, training.
I think the safety culture and certification process are the bigger problen now.
It seems Boeing had the rule makers (congress) and regulator (FAA) in the pocket over the last 8 years.
Boeing, congress and FAA fought shoulder to shoulder against the foreign competition.
Far reaching grandfathering of requirements and design was re-allowed, responsibilities delegated and FAA forcefully "Streamlined"
JATR recommendations and GAO reports are 100% contradicting on FAA aircraft certification & it is totally clear to me who the more objective:
Congress (GAO) 2017:
https://www.gao.gov/assets/690/683649.pdf
JATR 2019:
https://www.faa.gov/news/media/attac...A_Oct_2019.pdf