In 1.2.0.81 Realms, People besides the owner of the realm that are assigned the role of "operator" do not have access to Multiplayer settings, and cannot change settings in the realm. Later on, after players have been given the operator role, they lose it for some reason.

The images show me, a set operator of this realm, unable to access the "Multiplayer" menu, in which I could change settings around. While I am not the owner, the owner has tried giving me the role of operator.