Mods extend the life of games, which means you aren't buying new games. I've don't think mods will ever be part of the cloud gaming scene. Cloud is the ultimate DRM. Need people to buy the new version of the game, even if it is worse? Remove old game from servers so they can't play it anymore.
The overlap of modding and multiplayer is small and usually for coop-ish games where cheating isn't a big deal. Most big modding scenes are for single-player games.
Unlikely to get your nude skyrim follower mods though.