I understand the direction of your comment, engineering doesn't guarantee security either.
Hubris is the single biggest downfall, whether it's pegged on insecurity, or a false sense of knowledge, superiority or entitlement.
The very best and most experienced people I know have deep expertise, and maintain a healthy mistrust of their own work to keep an eye on it and improving it.
Real world experience and run history is a big thing, and people can re-learn the lessons of the past over and over with their egos, or also be open to learning from others to learn quicker.
It's not hubris (for the engineer) in this case though. It is the fact that company X knows that its dept Y can thrive with 10 engineers, and stay afloat with 5 engineers, so the magic number is 5. And then it is down to the individual to convince their manager (or resign) that problem_A is bad, but problem_B is worse, but not in my P&D objectives.
I am ~50, I have worked (now..) 20? 20+ years in Audit/Compliance, and I laugh-cry inside.... and I am NOT surprised when I read about cases like this, it's another day in the office/life..(definitions)
The terms hubris, ate, nemesis, and tisis originated in ancient Greece and had specific meanings and roles in everyday life.