Peng Qi
Emperor
Well, let's list all of the things that remove you from immersion in Civ IV then, and compare them to V. I will leave out things they have in common.By "simulation" I am referring to the sandbox "build your own civilization" element of the game, not having everything play out in a historically accurate fashion.
IV:
-One Resource=Infinite Quantity; this means almost no conflict over resources, which is the primary reason for real-world conflict.
-More Cities=Less Money; this has never been true.
-Global Warming=Tiles Randomly Change.
-Nuclear Plants meltdown constantly.
-Huge armies of axe-wielding marauders are the norm.
-Countries forced into positions of vassalage love their masters.
-Colonies cost, rather than generate, huge piles of money.
-Forms of government are unlocked by technological, rather than cultural, advancement.
-Gold is worthless to your citizenry unless you adopt universal suffrage.
-Vassalage improves the quality of your units for some reason.
-Bureaucracy is most likely to be found in small nations.
-Can't draft citizenry without adopting nationhood, even though peasant levies were common in the middle ages.
-Slavery involves mass-murdering your own populace and apparently constructing things out of their corpses.
-Serfs are a more effective labor force than non-serfs.
-Having a caste system removes the need for your scientists (and other specialists) to work in scientific buildings (and other buildings).
-People around the world, even those who have never heard of you, get irritated with their leaders if you have "emancipated" your population and they haven't.
-State Property somehow makes larger empires cheaper to manage.
-Environmentalism increases civilian health for some reason.
-Theocracies field better troops for some reason.
-Pacifism is a national civic.
...you know, this is taking too long. I think you get the point.