Rabbit, this is the government telling the civil servants what kind of language is useable given their policy. They're entitled to do that, as the elected government directing the appointed government. What you or I regard as plain speaking or whatever is irrelevant. The elected government is the boss, the civil servants are the employees. The boss is entitled to dictate what the employees can or cannot say in an official capacity. If the employees don't like it, they can say what they like outside working hours, or quit their jobs and say what they like when they like.