I vehemently disagree on the too complex front. If there is any inability to X going on in the FAA it is because of a culture of continual budget cuts hamstringing the ability of the agency to acquire and keep talent.
The current incarnation of the FAA is a joke. This is not some bureaucratic paper pusher organization. This is the agency responsible for the overall architecture and requirements that historically made the American Aerospace industry a force to be reckoned with when they weren't being blindsided or hamstrung by excessive political pressure by industry.
My proof?
There is nothing complicated, about the trim system of a 737 MAX. I've sat down and done a bit of research, reverse engineered the basic mechanical components of the system, and I'm just some bloke who had a few hours to kill on the weekend.
It's a highly geared mechanical gear train, with a secondary set of electrical motors, connected to a jackscrew, which drives the horizontal stabilizers while feeding back electrical actuation information back to the pilot's via the mechanical gear train. At some point, they wired in extra electrical connections from whatever black box MCAS is implemented in into the command circuit for the electric trim motor, and called it a day.
There is nothing complicated there. It's a basic composition of simple machines. The complicated part is the implementation and logistics details, in addition to making sure at some point, all those pesky details are written down, all those integrated systems are tested/verified to be of sufficient quality, and that each component has an audit trail to be referenced should investigation be necessary.
All that extra information is required specifically because it has been found to lead to increased safety over time. The FAA's duty is to ensure at a minimum, every player is living up to and respecting that standard. Something the history of budget cuts and delegation of authority to manufacturers has very clearly jeopardized.
I don't like the FAA. I'll never even be able to take the physical pilot training to fly because of the draconian nature of their medical certification regulations, but I can't even argue that they are unjustified in terms of the catastrophic outcomes that are prevented by having them there.
It is possible to hold a manufacturer to standards via external impartial audit.
It is difficult to do so if you can't even support the billets for a set of Subject Matter Experts who don't need to resort to alternative revenue streams so they can concentrate on doing one thing and doing it well.
There just needs to be the realization that at some point there must be a figure in the relationship between operator and manufacturer with the capacity, nay, responsibility to stop something which has not met the minimum standards of airworthyness.
It ain't physics that's the problem, it's the people. Machines don't lie. Even when malfunctioning, they're telling the truth in as much as the physical principles they are subject to will allow.