it mentioned...

"conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction)."

hmm exact same... must not me fast enough to counter thrust. 1000 MPH conveyor to counter a 10 MPH thrust does to mean equal speed does it? Doesn't say anything about stopping movement just matching speeds.

If you change the senerio, no the plane doesn't fly if thrust is negated by friction as stated numerous times before.

If you follow the scenerio then the plane flys without much additional effort.