Jinchuriki were initially used to balance the power of Tailed Beasts between the nations, but the Akatsuki ruined that balance by stealing away the Jinchuriki. In addition, the balance of power as well as the weapons of war they represented became unnecessary as the world moved towards peace. The Five Great Nations are now all allies with one another, so the Jinchuriki have no purpose to aid in the balance of power when the villages all trust each other.