The plane's engines generate thrust which pushes the plane forward. You could have the conveyor moving the wheels at 20 times the speed of the airplane and make almost no difference. The engines provide thrust in relation to the plane's position in the air, not on the ground.

Think of it this way: If the wind is blowing against the airplane's forward motion, does the airplane stop flying when it's groundspeed reaches 0? No. the plane is still flying at whatever speed the engines provide thrust for, only forward progress on the ground is nil.

Now take the same plane and put the wind behind it. Now it's going as fast as the engine provides plus whatever the windspeed is in relation to the ground. The airplane doesn't know it's going any faster.

If the airplane is on the ground as in the conveyor scenario, the wheels are simply tracking along the conveyor minding their own business having nothing to do with the rest of the airplane's operation. They can go faster or slower and it makes no difference to the plane. The engine's thrust provides forward motion in relation only to the air around it, and no consideration is taken to the speed over the ground, however it may be perceived.

Here's an interesting example. When I was in flight school we used to have to chain the wings of our planes to the ground. This was done because the wind could (and I saw it happen on more than one occasion) pick the plane up off the ground. At this point the aircraft was indeed flying, even though chains were holding it in one place in relation to the ground. It's quite interesting to be walking on the tarmac and suddenly every small plane appears to jump up into the air and hover for a bit, then settle back to the ground. Sometimes there might be one porpoising because a flight control surface was locked or jammed or something.

The bottom line is this; If the conveyor had anything to do with the flight of the aircraft, you could assume that merely leaving the ground would cause the loss of all forward thrust and the plane would come crashing back to earth.