The National Party, thinking itself the "natural party of government" with an inborn right to rule, are upset that they are not being consulted about who will be the next State Services Commissioner (something they have never done in the past, and which they are never likely to do in the future, but hey, what's hypocrisy when you can pretend outrage?). So, they're threatening people in an effort to discourage them from applying, with an implicit threat to fire them based solely on who they were appointed by.
They call this "returning neutrality to the state service".
Fortunately, the State Services Commissioner can only be removed for misbehaviour or incompetence, on a vote of the House. You'd think the National Party's spokesperson for the state sector would know that before mouthing off.