I think the whole point is that the lead dev has pulled you into his realm, he is not Eorzean or even of Ethyrs, it would make less sense if he spoke as they do. Further he is talking to you the player, not you the WoL.

But for me it's fun. I like learning new words, the feeling of "Oh, English can do that." or "That's really not made up?" is enjoyable to me.