You speed up to a 'terminal' velocity around 70 mph. You've probably put your hand out the window of the car at 70 mph, so imagine that on your whole body. Now think of sticking your head out the car window and trying to talk. You'd really have to shout! I don't know if you could make a phone call or anything.
And it would depend how high you were. Commercial airlines fly at tens of thousands of feet, and anything over about 15,000, you're going to have trouble breathing, let alone talking. It isn't oxygen, it's the density of the air (but yeah, you don't get enough oxygen.) If you fell out of an airplane at 35,000 feet, I don't know if you'd freeze first or suffocate first.