Looks like this was just copy-paste without any thought into whether it
should exist. It really shouldn't exist.
This is a thing for the playlists system because the *whole system*
there relies on polling the web API to get updated information. In the
case of mutliplayer, we hand off all communications to the realtime
server at the point of joining the rooms.
The argument that this was there to do faster polling on the selection
isn't valid since the polling times were the same for both cases.
Closes#11348.