Ok ok, when you mentioned regardless of what the conveyor belt is doing. I think you still mistunderstand the concept of the conveyor belt here.

The conveyor belt is moving at a constant speed to match the forward speed of the aircraft so the aircraft is effectively stationary. The conveyor belt accelerate at the same rate as the engine would accelerate the aircraft. Effectively canceling it's forward rolling speed.

Elliminating the conveyor belt, and let's say use an alternative method to keep the aircraft stationary at the same spot- wheel brakes.

Will the aircraft lift off?

There's another clip that support the 'no' camp argument. By, guess who? The one that busted the myth themselves.



Problem with this argument is, not all the aeronautics experts are in the same camp. Asking several engineer from Airbus/ Boeing / Bombardier/ Embraer may yield different answer. So far the debate carried on because experts in this field are yet to come together to give a definite answer.