Question: you have extensive experience with iron sights. What about the hunter who doesn't have that experience - wouldn't a scope dialed down to 1x (or 1.7x in some cases), maybe illuminated, be more appropriate for that hunter?
Based on experience in the military and practical shooting fields, at very short range even at 1x (no magnification) a scope is slower, even with both eyes open, than a set of iron sights, and iron sights themselves are slower than just looking down the barrel. Reflex or holographic sights are faster than scopes or tube-type red dots, because their field of view is "almost" unencumbered, but
your brain still needs to guide the front sight or red dot on the target, which is slower, until you have a whole lot of practice doing it, than your muscle memory pointing and shooting. If you want to verify for yourself what I just wrote, take a Remington 870 with a shotgun barrel and a slug barrel with rifle sights on it, and go trap or skeet shooting, alternating both barrels. This is a very enlightening experience...
This reminds me of the user manual for the .32 Seecamp that has been for decades the gold standard, loaded with Winchester .32 Silvertip, of LEO (law enforcement officers) last-defense backup-gun. These tiny pistols have no sight. None. Zero. Not even a groove. Their first generation user's manual had a sentence along the lines: if you need to ask about sights, this is not the gun you need. Their current user's manual states: "The Seecamp is designed strictly for self-defense ... Crimes usually happen under bad lighting conditions at short range ... If you can't hit the target pointing and shooting, be sure to have a good lawyer lined up to explain why your life was threatened at a distance where you needed sights."
.32 Seecamp and its wallet holster, the ultimate LEO backup gun, and civilian deep-conceal carry gun. Strictly a short range defensive affair. No sights needed. As the leather shows, this has been my back-pocket daily companion for many, many years, from three piece suits to beach shorts. The user's manual states: "The Seecamp is designed strictly for self-defense ... Crimes usually happen under bad lighting conditions at short range ... If you can't hit the target pointing and shooting, be sure to have a good lawyer lined up to explain why your life was threatened at a distance where you needed sights."
Regardless of which sights are considered, a hunter has no business following up wounded DG, especially cats at bayonet range, unless hundreds (more like thousands actually!) of shots were fired under pressure at close range in practice. Otherwise, said hunter is but an additional liability to the PH. Shooting in a couple of friendly local USPSA (United States Practical Shooting Association) rifle or shotgun events will likely open your eyes as to how much NOT ready you are to follow up a wounded buff or cat. I had done a fair amount of "kill house" live fire training in the military in my younger years but I was amazed and humbled to see how much proficiency I had lost over the years...
Here are some easy and also very enlightening exercises to do alone or with a couple of safari buddies:
1) Put three milk jugs (or three 6" steel plates) at 15, 10, and 5 yards. Set your smart phone timer on 5 seconds. Load 3 rounds in your DG rifle. DG charge stopping proficiency starts when you hit squarely all three jugs/plates, predictably, reliably and repeatedly, in less than 5 seconds.
2) Download a practical shooting App that will clock your shots after the buzzer sounds. Hang a milk jug (or 6" plate) at 10 yards (you can change the height from 5 to 2 feet to simulate buff or cat). Load your DG rifle. Wounded DG follow-up proficiency starts when your first shot hits predictably, reliably and repeatedly the jug/plate squarely in less than 2 second (1.5 preferable).
Try it, it is great fun and great practice
Chances are that regardless of whatever optical sight you have on the barrel, you are faster without it - hence the need for quick detachable mounts - unless you truly burn thousands of rounds with a reflex or holographic sight, in which case, you will be marginally faster but mostly more accurate with it. This is why SOCOM (Special Operations Command) purchases EOTech holographic sights and trainloads of practice ammo...
Then, of course, the conversation can shift onto whose job it is to stop charging animals, how often charges happen etc. etc.