Many of the top titles on both Vive and Rift are multiplayer (Elite Dangerous, Battle Dome, Eve Valkyrie, Tabletop Simulator, Hover Junkers, Pool Nation VR, etc.) and that's only games, ignoring purely social multiplayer experiences like AltspaceVR. I'm not sure why you think there is a lack of multiplayer content currently or in the pipeline (Project Arena, Ripcoil, The Unspoken, RIGS )...