No kidding.
It would take them more than 4 years to make a game of that scale and the player would be too overwhelmed by the massiveness.
I doubt I'd be overwhelmed, although it'd certainly give me a headache to think how much effort would have gone into a game set on an entire continent.
All those quests, all those NPCs, all those dungeons, all those tribal bastards who don't like Argonians...