Because 0G is a (slightly imprecise) term for weightlessness, and weightlessness is by definition when the only force acting on a body is the gravitational forc

Because 0G is a (slightly imprecise) term for weightlessness, and weightlessness is by definition when the only force acting on a body is the gravitational force. If you're in an elevator, and the elevator cable snaps, you'll be in free fall (at least initially), although you are nowhere near the escape velocity.