The maths behind zero power for an infinitely long wing don't take account of the fact that the Saturn analogy is a closed loop. Imagining a flat plane with an object above it, infinitely long in all directions, then surely if there is a gravitational force, the object and the plane attract each other. Unless they orbit each other, (like Saturn's rings orbit Saturn), then they will move toward each other. Surely the particles in Saturn's rings are in perpetual freefall, just like satellites orbiting earth? Without that motion around each other, the infinite wing would still need something to keep it in the air?
Obviously with a wing around the earth as a single body, the pull on one side would be counteracted by the pull on the other and it would float, or in other words the earth would be pulled toward each part of our ring equally. The difference being that this is a single body and that Saturn's rings are many bodies.
I realise it works mathematically, I'm just saying I find it hard to conceptualise how it would work in reality.