A lot of issues with gun fight information is that nothing is very consistent. One perp will die on the spot and another shot in basically the same place with same or larger caliber will go on to kill a couple more people, or live long enough to get in surgery and be repaired. Same for the 'good guys'. Some people will 'give up' after being shot in a non-lethal location (eg, arm or leg muscle) while another will take hits to vital organs and go on fighting. And, it has less to do with caliber/bullet than it does the person.
Just read some Medal of Honor citations. People were shot multiple times, even having legs or arms severed, and they still manage to continue to fight.
There was a study done of shootings over several years and over a thousand incidents that described as best it could results of caliber (sorry I can't find my link to it). About the only conclusion it made was that shotguns and rifles are better than pistols and pistols less than .380 were marginal (many failures to stop). The problem with the data is the lack of data. There just are not that many cases of someone being shot with a .44Mag for example. So, if one person being shot with a certain caliber weapon and not stopped mean much or was it just because the shot was not placed properly? And much of the data was not very complete, ie, was the shot recorded in the ER the only shot fired or was it one of 20 and that one just happened to hit the person?
I do agree that,
everything else being equal, a bigger (and maybe faster) bullet MAY be better than a smaller one. But, is a brain shot with a .380 going to make the person less dead than a brain shot with 00 buckshot? Will a 9mm that severs the aorta be less effective than a .44 that does the same thing?
In my mind the larger, faster bullets make a difference when non-CNS organs are hit. The possibility that the person will react more to a larger, faster projectile is more likely. OTOH, I know of two people who were 'blown off their feet' (their words, not mine) by .38 snub nose revolvers using ball ammo. One was hit in the upper arm, the other in the thigh (no arteries severed).
So, cherry picking an incident to make a case does not seem worthy of making a general conclusion. It is valid as a cautionary tale, that your .500 S&W may not cause the victim to immediately flop over on his back and die.
I do like to bring a gun to a gun fight, since I am not skilled with knife fighting. Which gun? I have several and any one may serve me well if I shoot it accurately. And, yes, I do carry extra ammo