I genuinely don't want to offend or get personal, S7700, but do really mean what you said?
Start looking at the end result here and regardless of what caused it, what would have been done to avoid it. ...
How do you come up with sensible ideas to avoid an end result, if you don't know the cause/s of the end result? It seems to me that that which should be done to avoid the risks arising from e.g. an unnoticed rudder trimmed to FSD is not the same as that which should be done to avoid the risks arising from e.g. unnoticed power level migration. And if there was a failure which no competent pilot could adequately overcome to save the aircraft, what then?
If it was a rollback, what can be learnt from it?
I'd suggest something different than if it was unnoticed rudder trim at FSD on take off. The first question that would arise is: What causes PLM in this type of aircraft? Should it happen in the first place?
There's a difference between a system design flaw or defect and the proper avoidance response to that problem, on the one hand, and a pilot's failure to use the system properly to prevent or reverse the migration, and the proper avoidance response to that problem, on the other.
On my interpretation of what grogmonster has posted, unnoticed PLM on this aircraft type is a far more dangerous situation than unnoticed rudder trim at FSD, with the former rather than the latter more likely to have resulted in the aircraft ending up where it did.
If it was engine related, it doesn’t change the outcome other than a witch-hunt to the manufacturer or maintenance organisation, but what does matter is how the event is handled.
Goodo, then. ATSB, CASA and us 'Monday morning quarterbacks' can confine our witch-hunts to pilots.
One wonders why they bothered grounding the Max 8s. Any competent pilot should easily be able to handle the consequences of MCAS activation on erroneous input from an AOA sensor.