Exactly. Which has nothing to do with resting for 8 hours every day.
I fail to see what point you are trying to make here. In Baldur's Gate in some instances and especially Jagged Alliance resting has its importance exploration wise. Aside from resource management (and tiredness) not only in the tactical map but also at the same time in the strategical-exploration map (distances) there are times where time is a factor. For example Minsk in BG1 needed you to complete his quest under three days. In jagged alliance OTOH time is a constant strategic factor.
In 4e time is a factor regarding encounter resources too. It is only connected to the management or rather tracking of a simple level though (you either have the daily resource or not and you know very well when this happens (when and how you can regain it) -not consumable strategic ones that you can balance them in the various ways you can choose that can create this open ended effect. Of course this does not mean you cant have exploration decisions because of it, but it does not help either. You will have to add more stuff.
But adding more stuff to a 4e game is not such a good idea IMO after a certain point. The game is robust tactically will various tactical solutions a player would need to keep his attention on. Adding more things can make the game really complicated for your average player.