"OK, The $64Bn Question - 737 MAX. Root cause?"
The Aircraft Certification Process Review and Reform ARC - FAA of 2012.
https://www.faa.gov/regulations_policies/rulemaking/committees/documents/media/acprrarc-4202012.pdf
Pushed by the 787 development & certification drama's, the A320NEO sales boom, Industry & Congress closely worked together to Streamline aircraft certification processes, delegate responsibilities to OE's, to improve competitiveness of the US Aerospace Industry.
Congress and Industry representations made sure in the years after set
Congressional directives & KPI's were met using FAA budget Reauthorizations.
2016
“Aviation manufacturing is our nation’s top export and general aviation alone contributes approximately $80 billion and 400,000 jobs to our economy,” said U.S. Transportation Secretary Anthony Foxx. “The FAA’s rule replaces prescriptive design requirements with performance-based standards, which will reduce costs and leverage innovation without sacrificing safety.”
https://www.faa.gov/newsroom/faa-iss...tion-standards
A root cause everybody has been trying hard to ignore / forget. Because most key actors are still around.
It allowed short cuts & aggressive grandfathering of design and requirements for the 737MAX (& 777x) 2012-2018. Saving costs & time.
During 2012 - 2018, "Efficiency goals" beat "maintaining the highest level of safety".
Bureaucratic, slow FAA didn't stand a chance against Industry (Booming Boeing) + Congress + Public opinion.