My experience is that a basic level of manual flying ability is retained and available in the highly unlikely freak occurrence of loss of all autopilots,
I seem to recall the Egyptian 737 loss of control accident when the captain thought he had the autopilot engaged after take off but it wasn't so he quickly found himself in a fatal spiral in his attempts to hand fly on instruments. Result: Hit the sea at 406 knots.
Now, about that "basic level of manual flying ability is retained and available".....!?