Has nothing to do with "If you don't like the MMO aspect of an MMO, then don't play it. ", cause it does not get rid of that aspect at all, having an option to hide peeps is useful, and all the other multiplayer aspects are still there, and by your logic, why would they even have a player render limit in the first place :U they have half implemented hiding them already, why not just go further with it.
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Also it would only be on the client side anyways, who actually cares what peeps prefer to see or not :U it changes nothing about the game at all.