I don't think "nowhere near as complex as it seems" is anywhere close to describing what many consider the most complex game ever built, including many industry veterans. Every material has dozens of variables (such as density), every creature's limb acts differently, there are thousands of materials and object types and most are researched thoroughly.

It is the most complex simulation game ever created (though not the most accurate). The fact that it's not very hard to play as you'd imagine, does not mean it is not complex.