What's the actual improvement
I saw the headline and assumed that they'd come up with a unit that didn't need a driver; something like, a driver takes it to the gate and hooks it to the plane, then gets out. The pilot remote-steers it to the runway, where it disengages, and then returns autonomously to a parking space for the next go round.
This is - a driver drives the tug to the plane and hooks it up, the pilot steers it while the driver sits there, the driver unhooks it and drives it back to the apron. Which is exactly as it is now except for the pilot doing the steering. Still need one tug and one driver for every taxi out.