You tested this with a simulator, right? X-plane does not take into effect noise or lag. If you tested it with the simple simulator in our repo, then it doesn't even take into account the aerodynamic effects.

Those steep angles are called "unusual attitudes". These kinds of aggressive maneuvers are specifically trained for because the airplane doesn't behave like you expect it to. You are effectively flying a knife edge, which is not at all what was simulated.

In real life, the plane will enter into a very steep bank, and start to lose altitude. As it loses altitude, it will pull up on the elevator, which depending on the angle will either cause it to tighten the bank, or to start nose up. If it noses up, you enter into a spin when the plane stalls (higher g-loading leads to higher stall speed). If it doesn't nose up, then the tighter turn won't help as the plane continually descends. 

Both scenarios lead to crashed planes. This is why the standard rate turn for a plane is 3 degrees per second. I'm not suggesting we go that slowly, but we do need to limit our bank until we have good, real-world testing data. My real-world tests showed a maximum of 20 degrees before the simple dynamic model we use on our controllers was no longer able to provide good, stable results.