Aircraft dynamic stability (wing + tail + aircraft cg position) is very different than a free rotating wing on a pole (no tail, gravity play no role in wing rotation unless the boat is rocking).

Best case scenario is a symmetrical wing rotating on a pole at the aerodynamic center of the foil so there is no varying pitching moment with wind speed (CM=0). But also the CG of the wing need to be at the center of the pole otherwise when the wave rock the boat, it would create a moment that will rotate the wing and create lift, so a driving force and more boat rocking moment.

But still, nothing to do when the bearing jam! Something will go wrong!

PS They use crane to remove rigid wing from a boat ...