All to often I think the root cause is somewhat hidden in the complexity of circumstance.
The problem here is your deep seated psychological desire to find a single root cause. That's antithetical to safety.
I always find it odd that people choose to use the metaphor "root" because very very few plants have a single root. An individual plant has many roots, and in fact botanists speak of a individual plant having a "root system".
The complexities you mention don't "hide" the causes of the crash. They are indivisible from those causes.