it's absolutely possible to create complicated non simulationist rules. Now, I have no intention of using simulationist rules, especially for combat, but I like to read them none the less. It's almost like a separate intellectual interest almost totally divorced from actual gameplay.
I also like to write a lot of background stuff for my own rpg scenarios, even if I'll never actually use it for anything. I recently created a whole fake UN convention on space law based on shipping law just for fun, which I guess says a lot about what I find fun...