PlayerList#moveToWorld already untracks the player from the player list,
meaning that we do not need to worry about this untracking players
who've left the world, The server also untracks a player during
disconnect, handing yet another case.
If we don't need to untrack players who've left the world, it should be
reasonably save to do this, as we're not going to be performing any
server->client updates here, which is what this code is intended to do,
and all players should be untracked.