that the overall risk to aviation is very low
You don’t know this and have no evidence for this.
An altitude deviation, a misunderstood clearance early on in the flight?
There’s no testing required for these potentially high risk but eventually non consequential events.
So we’ll never know how many of these events are caused by fatigue, self medicating or while even slightly intoxicated.
We don’t know how many times a multi crew environment covers the induced errors.
Again, self reporting and self grounding is something different then getting caught and playing the compliant victim.