I think the question of ethics does and should change as conditions dictate, I have just trashed my antelope tags for the season because of a few factors. One time I had a very easy shot at 650 yds. , but It was a fawn doe and a yearling buck, no wind no mirage issues. Next time was a Nice fat doe about 700 yds. Could not get the Leica to read a distance, so instead of shooting ,just packed up and tried to move closer. Saw a whole group together one evening at 385yds, cake shot, but they were up moving around and never cleared apart enuff for a GOOD shot on any of them. Antelope are best eaten when shot bedded and not running all around the countryside. So my way of hunting is looking for bedded resting animals with proper conditions. With the amount of hunters here this year. I did not click the safe off. Distance , conditions ,terrain , rest, level of practice , general health of shooter , amount of time available( is it ethical to shoot in the last twilight of the day?) are all personal things that are accounted for IMHO
Ethic should be constant, independent of range or conditions or equipment or etal. That is, Absolute certainty of a lethal shot.
