System-level ACLs; mandatory or discretionary access control; secure-by-default application and network configurations are all for naught if you take an LLM, run it with all the privileges you'd have an accountable, judgemental operator, and then tell it to act based on arbitrary untrusted input which might include prompt injection attacks, something which cannot generally be sanitized.
Well-defined, well-enforced security policies can mitigate disasters, but many in the wild right now just don't account for this kind of threat model.
It took me less than 5 minutes to completely disable... nobody cared, they just kept going - check the box and move on.
Software "engineering" in particular has always been more than 50% cargo culting. Good engineering practices never matter when the alternative is just going through the motions of whatever rituals are in vogue.