NZ Politics

Right wing parties are generally hostile to collective bargaining because it gives workers greater power to secure better wages and conditions from employers. Even when that bargaining can also lead to productivity improvements through better trained workers, greater retention and so on.

This is completely consistent with the last times National have been in government. They effectively destroyed unions through the employment contracts act in the early 90s and they've never fully recovered, despite some moves to strengthen them when Labour has been in government.