From what I've read here, with arguments for different perspectives (if you don't mind me phrasing it that way ...), I feel confirmed in the idea that the high-ground rule has no real-life/simulationist justification. (Which is different from tactical/gaming justifications.)
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I'm still talking about one-on-one ranged combat (I understand the advantages for a medieval or early-modern army).
I'm sorry what? You really think that the high ground has no real world benefits. Maybe I'm reading your post wrong [...]
Yes.
It's all about the setting, and if I understood well what you said earlier in the thread, we are, in fact, mostly in agreement..
- When an army, with infantry and a battalion of archers, sits on a hill and a similar army comes from a distance, then the army on the hill will indeed benefit from the high ground.
- When two archers are shooting at each other, the one standing on a big rock, a wagon, rooftop or at the top of stairs, will not have benefits from the high ground.
The battles we fight in DnD/BG3 are small scale fights that usually erupt when both parties are already pretty close.
A couple more considerations.
* In a case of hunting/camping/sniping, the hidden (presumably high-grounded) archer is not seen by the target. 5E DnD already has a rule that gives Advantage to an attacker in that case.
* An archer on a fortification with parapet, or on a gallery with balustrade/railing, or who will crouch or step back after firing will get some amount of cover. 5E DnD already has a rule that makes the attacker less likely to hit in that case.
* As for spotting/acquiring target, again, in standard BG3 battle, we generally have everyone see everyone, broadly. If an archer has trees or pillars to hide behind (think : hall of priestess Gut), the other archer will lose sight of the target. This hold irrespectively of high ground or low ground. It's about your surroundings. In DnD, there is no cost for acquiring target, but you can't shoot at someone who is not in your line of sight. So that's kind of taken into account already.
If an archer is standing alone, on the edge of a rooftop, a big rock, or the top of stairs (think : Nautiloid helm), they are giving a pretty clean shot to any archer on a lower ground, which certainly doesn't make it harder for them to hit. And the high grounded archer doesn't have any benefit from their position.
