When I have seen this problem, it's because the sysadmins are instructed (or have learned via experience) not to explain their reasoning to developers or end-users. Because if they did, then it becomes a discussion or argument that becomes a time sink since there was very little chance they could change the mandate even if they agreed.

So they become intentionally opaque to move that discussion out of their laps and make it come via the development team managers confronting the operations managers and having the fight on that turf.

Such situations occurring is a sign that the organization is not set up effectively. This sort of confrontation shouldn't need to be happening.

Ideally the development team's lead and/or project managers are involved with, are informed ahead of time, or are even contributing to the policy decisions on the operational side.

Because telling someone that you did something because of compliance doesn't help. They still blame you personally even though the compliance standards are usually industry-wide or even defined by Congress as an act of law.