The trouble with that argument is that it applies to essentially any number of rounds a fellow might choose to carry. The huffy puffiness stems from the attitude, among certain folks, that they have a superior grasp of the subject and are therefore entitled to talk down to anyone who hasn't reached the same conclusions.
It does apply to any number of rounds, but those extra rounds give you breathing room if you dont make the perfect hits you do in slow fire practice at a static target when youre not under stress and you very well may need to continue to shoot.
If the target is moving, you are moving, etc., the target doesn't go down as you expected and continues to be a threat, those 5 or six rounds in most revolvers get used up pretty quick. And thats just "one" opponent. As soon as you add more, or increase the difficulty of the problem, things go south pretty quick.
One target with a revolver is doable. If youre well-practiced, two might be. Assuming you actually hit something that will bring about a quick stop, which is a lot harder than I think many seem to understand. Especially if the target is determined. COM is in no way a guarantee and is basically the choice, simply because its a bigger target with more chance of hitting "something". Its not the target that you really need to shoot to bring about a near-instant shot that many seem to think will always happen.
With any of them, you need to be able to shoot quickly, accurately, and repetitively, without hesitation, and without having to think about doing it.
This isnt about talking down to anyone, I think its about being realistic. From what Ive seen on the various ranges Ive shot on over the years, and with many people I know who have and carry guns, most of them/us WAY overestimate their skills and really dont put in the time and effort to be even reasonably and "realistically" proficient. And that goes from administrative handling through shooting. Its about more than just "shooting".
Just to get to be "reasonably" proficient takes a LOT of time, work, and ammo. Not to mention dryfire. How many people do you know who currently carry a gun, are actually putting in that effort?
Are 5 rounds enough? Are 17? Who knows. I just watched a video the other day where a cop got into it with a guy in a traffic stop, just literally feet apart, and in the matter of less than a minute or two, basically emptied his Glock 21 three times, hit the guy something like 15 times, with a number of "vital" hits, including three in the head, and he wasnt yet dead when they got him to the hospital.
Lets see....how many revolver reloads is that?