Personally, I think it depends on the sitch. Something immutable would probably be the better go for people coming from Windows and would help with IT costs since all systems would be, at their base, the same. No one is going to accidentally install something that breaks their system. And the main drawback of immutability (less control over the system) wouldn't be a problem because people shouldn't be installing things on government systems that are outside the scope of their job.

EDIT: In a sentence: a good distro is one that's good for your organization.