Turns out, this rule was not from IT. It was a requirement from the cybersecurity insurance policy the organization had taken.
I wonder if some of these constraints are to try to find a way not to pay out on the policy.
To bastardize Douglas Adams: For-profit insurance is a scam; breach insurance, doubly-so.
"Why did this stupid shit happen? Oh, it's money again."
If you, the person in charge of these decisions, allow an incumbent policy - even a bad one - to stand, then if something goes wrong you can blame the policy. If you change the policy, though, then you're at risk of being held personally responsible if something goes wrong. Even if the change isn't related to the problem.
It's not just cybersecurity. I have a family member who was a medical director, and ran up against it whenever he wanted to update hospital policies and standards of care to reflect new findings. Legal would throw a shitfit about it every time. With the way tort law in the US works, the solution to the trolley problem is always "don't throw the switch" because as soon as you touch it you're involved and can be held responsible for what happens.
we've gone through HITRUST several times and I just told them we weren't going to do forced password rotation since NIST had updated their guidance. it was fine!
and every time we get a vendor security questionnaire I just say "no, we don't do this because it's old guidance" and link to NIST... no one has ever complained.
After all it's perfectly possible to do interior work in your house that isn't up to code, but if it burns down in a fire, the insurance company will investigate and may not pay out if they find out.
It’s usually on the checklist for some audit that the organisation wants because it lowers insurance premiums or credit card processing fees. In some cases it’s because an executive believes it will be good evidence for them having done everything right in case of a breach.
Point being the people implementing it usually know it’s a bad idea and so do the people asking for it. But politics and incentives are aligned with it being safer for the individuals to go along with it.