Comment by BWStearns

It's like swimming in a stream. Even if you did nothing you would move basically at the rate that the water is moving.

Lift only comes from the interaction of the air and the wing, so if there's zero relative motion then you will fall out of the sky, regardless of if you have a 200 knot groundspeed.

This also means that, if the wind at altitude is above your plane's stall speed, you can hover in place by flying straight into the wind! (example here: https://www.youtube.com/watch?v=n_e6ijREScE)

Similarly, if you are in a packet of air that is moving at 200 knots, the fact that you are moving at 500 knots indicated airspeed does not mean you are flying supersonic from an aerodynamic perspective, despite having a groundspeed of 700 knots.