There is always a chain, but the objective is to fix as many parts of the chain as possible. Check out American Airlines 191 as a classic example. The "root cause" was maintenance not being carried properly, which caused pylon damage resulting in the engine detaching at takeoff.
This would have been survivable but numerous other things contributed to it being an accident that killed everyone on board and some people on the ground. If the single engine checklist was different, if the wing slats had a backup that prevented them being forced down when hydraulics failed, if both sticks had been fitted with stall shakers, etc, etc they would have gone around and landed safely. These issues were all addressed after the investigation.
Eliminate as many parts of this chain and even if the root cause happens again, people still survive.
Not that I am disagreeing with you that this guy is a total dick and MCAS is an abortion of a hack of a kludge of a system.
Biting the hand that feeds IT
