> It's noticeable how few computer wargames simulate any of this, instead allowing for frictionless high speed micromanagement.

Games are entertainment, and as with a novel or film, the authors pick and choose to get the level of verisimilitude they think the player/reader/viewer might want. Who wants to take an in-game break to go to the bathroom? When you pick something up (extra ammo) it's instantaneous -- and how come there are so many prefilled magazines lying around anyway? And when you get shot your shoulder doesn't hurt and you don't spend any time in the hospital.