I know nothing about the mechanics, physics, or aerodynamics of helicopters but a chopper pilot’s mother once described that flying one is like balancing one bowling ball on top of another. Hard to know what this means exactly but this description conveys the level of complexity and the two-hand, two-feet, moment-to-moment coordination required to fly a chopper. In contrast, planes do a good deal of gliding and are, in general, less complex machines. But you’re right in that this ultimately comes down to money as I’m sure autopilot is a possibility.