Everytime I think I understand async await, I get painfully reminded that I don't.

Async-await introduces the uncertainty of multiprocessing to single-threaded programs. You asserted that this subsystem which is accessible with a nullable reference is loaded? Cool, now let's call a function on it but uh-oh! The subsystem is now null because in the arbitrary delay of the microtask queue an IO event that causes the subsystem to unload had just exerted its effect.