The way this clicked for me (it took some thought!) was to see it as a lever, or at least an analogue to one.

Imagine a lever with the fulcrum on one end, attached to the ground. Wind pushes on the middle, and the car is at the other end of the lever. So wind exerts more force with less speed, and the car moves forward with more speed but less force.

That's basically what the linkage and gear ratio between the wheels and propeller do; it's the counterintuitive power flow that makes it so confusing...