The FAA lacks the depth of knowledge and experience to properly oversee Boeing's aircraft development, or the operations of a very complex major airline. They designate "Designees" among management at Boeing, airlines, and other suppliers etc to be their expert in the field. While this seems a bit in-bred (and it is), this basic relationship has taken a system with many fatal accidents a year, to zero fatal accidents most years, despite flying 10-100 times more flights per year. For the most part, it has functioned spectacularly well. We can thank our current level of aviation safety to this system.
But sometimes it appears, the system goes off the rails. Boeing has made some catastrophic engineering and production decisions over the last 10-15 years. Their FAA Designees have, at a minimum, lacked sufficient oversight and reporting to the FAA. More than likely, they have allowed the "in-breeding" to corrupt their decision making, and perhaps motivations.
The FAA, at the upper levels, have allowed this to pass. That might be a generous characterization, and the reality might be much worse. I really don't see anything going on in the public domain that makes me think they are fixing the system.
I think at this point they need outside assistance to investigate their institutional disfunction. They have been living in it for so long, it is their "normal".
I have a reasonable amount of time in the 737 classic and NG, and got my hours' worth of CBT time for the MAX, but never flew it. I thought the MAX was an abortion before I ever heard of MCAS, or knew of Boeings' problems with it.
I always wondered if they subjected the MAX to a full certification, circa 2017, if it would pass. Lots of things have changed in 50 years, including the physical ability, experience, and training of the pilots qualified to fly it.