To survive a runaway trim, pilots had to know the rollercoaster maneuver and have enough altitude to aerodynamically relieve airloads off the jackscrew so they could manually trim the plane back. If FAA and many others knew this then they should have instantly communicated it to all boeing max pilots. Instead none of that happened.
On the MAX's, the switches only kill all electrical input. So those procedures literally didn't apply.
The root cause here is "Boeing management wanted to get a plane out quick so they didn't lose market share". The way to examine the system and make sure this doesn't repeat (for now...) is to put someone in jail for it. Then the next time that some plane company wants to cut corners and get an unsafe plane out quick, some manager who doesn't want to go to jail will put a stop to it.
Show me the flaw in my logic.
In this case you're proposing to punish the smallest cog in the machine, some middle-manager or executive at Boeing.
It would be just as logical to throw every single American in prison for around 45 minutes (~1 person dead in 737 MAX crashes for every million Americans, 80 years (let's call that life in prison) / 1 million =~ 45 minutes).
After all those are the people responsible for electing the people whose job it was to oversee Boeing. Shouldn't we blame them for their disinterest in the activities of the FAA? Maybe give people who complained about the FAA's rubber-stamp regulatory policy before the 737 MAX parole?
All you'd accomplish by throwing people in jail is to incentivize these companies to restructure decision making to be more diffuse, and make all subsequent air crash investigations much more difficult due to everyone involved being afraid of having made some prison-worthy mistake.
Because the usual argument is that the C-suite and especially the CEO are personally responsible for the successes of a company.
So it's not unreasonable to hold them personally responsible for the failures too - especially when those failures amount to suspected criminal negligence.
This is not the same as assuming guilt. Due process should still apply.
But the risk of personal liability should absolutely be present as a deterrent.
And if some executives don't want to operate in that environment - that's absolutely fine. The system should encourage responsible actors, and allow the removal and punishment of those who prefer to act irresponsibly.
These people make tens or hundreds of millions of dollars in compensation, truly obscene amounts of money compared to the workers they manage. Why should they live risk-free lives when the lives of so many people rest on their decisions in the C-suite office, and their decisions are clearly not made with safety in mind, but rather profit?
Your argument is like claiming that a taxi company owner should go to jail when one of his drivers rapes a passenger, even if there was no way the owner could have known the driver had this propensity. It's totally nonsensical.
The executives at Boeing are the ones ultimately responsible for the decisions that led to these crashes, because they prioritized profits over safety, and directed their engineers to work towards that end. For that, they should go to jail.
I'd say some time after the first accident it was reasonably well understood what had happened, and the FAA (and many others!) concluded that it was still safe to fly the plane, as the pilots could easily interrupt the accident chain by doing the right thing quick (as the pilots on the Lion Air flight preceding the accident flight had done).
Why that assessment was wrong is a complicated story that has to be examined carefully.
From what I gather, in aviation safety circles "jail time" is very rarely considered a wise answer. As soon as you threaten jail, people will cover their ass and obstruct investigations. Instead, the goal is and should be to examine the entire system to ensure accidents don't repeat, and by and large, the system works exceedingly well.