And I don't see designers relinquishing that much control. I imagine they'd like to directly specify, for instance, what sort of rubble gets created by a collapsing wall, and how that rubble interacts with the player. Let's say you want the player to be able to take cover behind fallen debris, or you want the player to be able to destroy shit without impeding their progress around the map ... do you really want to rely on some heavily indirect process to result in the appropriate debris, or do you just want the programmers to say "here is the probability distribution of debris size when this wall gets destroyed".

It's all very well to enthuse over these low level procedures when they are just going to be used is a cosmetic way (aka 3d nerdery in movies), but once those mechanics start affecting the gameplay, they are pretty much diametrically opposed to the sort of game mechanics that you want (they aren't readible, for starters).

EDIT: having said that, if you did model walls as individual bricks glued together, and destroying a wall was just destroying the glue, then that would make a lot of sense from a gameplay pov. But that's a far cry from simulating tiny atomic elements ... it really just shows that you want to simulate at an appropriate level, not that you want to simulate at a super low level.

It's like, here in the near future, we have this awesome 3D holographic chess set with super realistic animated characters. It'd be a good idea for the game designers to model every fold, crack, and seam on the characters because that's what people will notice. The more detail you have on that front, the better. They won't have to go so far as to model a fully functional digestive system on each of these little characters for the sake of realism, though. There comes a point.