High ground does give advantage in real life combat; and there are plenty of reports of people exerting themselves amazingly for short periods (historical berserkers come to mind).
If you think it's easier to hit a target 100m away from you with a bow when you're higher in comparison than if both of you are on the same level... You never try archery...
In arena such in BG3, you wouldn't have any advantages in real life because most of the time, there isn't any obstacles
You are correct higher ground and distance is bad for both accuracy and power for an individual archer to hit a target. The closer you are to the target the more damage and accuracy regardless of bow weapon. Height or elevation from the target makes little difference where the archer aims at said target.
The shortest distance between two objects is?
The longer the arrow travels the less energy it has.
Higher ground gives a gerographical military advantage not "my weapon gains accuracy and damage" at higher ground advantage.
