Yes, but with planes and ships (on ships it's almost always called track pilot and speed pilot, by the way) you can let go of the controls for extended periods

Yes, but with planes and ships (on ships it's almost always called track pilot and speed pilot, by the way) you can let go of the controls for extended periods of time. In cars, right now, that's a recipe for disaster. Functionally they may be the same, but practically speaking it's very different.