When you really think about it, it's amazing that quill stems were in wide use up until the late 90s. You would think that steering a bike using a threadless-like device would be more intuitive than using the friction between the wedge of a quill stem and the inner wall of the fork tube

Although, now that I think about it, phrased a different way threadless systems are still a result of a friction interface between the stem clamp and the outer wall of a now longer fork tube.

Is there any difference other than weight between the two systems?