How come the stuff the simulation can do is so trivial?
It takes more than just a computer to fly an Apollo LM or CM. At the very least, you need simulations of the spacecraft’s IMU, AOT, and of the physical spacecraft (i.e., acceleration, torque, fuel usage, etc.). Maybe we’ll have those things, one of these days. The LM-Simulator module has made a good start towards providing some of these things.