By default, nodes such as renderSetup, renderSetupLayer1, collection1, and so forth are hidden in editors such as the Outliner and the Node Editor. Enable Options > Display Render Setup nodes in editors in the Render Setup editor to show them. You must also disable Display > DAG Objects Only in the Outliner menu to see them there.
Exercise caution when you enable this option, as deleting any of these nodes may produce unexpected results.
This topic refers to a different workflow than that outlined in Filter and display only render setup members in the Outliner, which describes how to streamline the Outliner to display the members of your collection such as your model, or your shaders.
You can disable this option at any time while your scene is open.
This setting is saved with your preferences in the option variable renderSetup_displayRSNodes, and persists upon restarting Maya.
You can also control this option by setting the environment variable MAYA_RENDER_SETUP_DISPLAY_RS_NODES. A value of 0 disables the option, and a value of 1 enables it. The environment variable takes precedence over the preference. Once the environment variable is set, the Options > Display Render Setup nodes in editors menu option is greyed out and follows the value of the environment variable.