What it's down to is placement, penetration, and maybe diameter, if you can get it without sacrificing the first two. We can generally place rounds much better if they aren't beating the **** out of us; penetration is almost purely a factor of tuning bullet design rather than the cartridge that launches it; and diameter isn't going to vary more than a few tenths of an inch with any gun we'd likely carry. If getting that diameter gives you a harder to control pistol that is either placing your rounds MULTIPLE inches from your intended point of aim, or it slows you down to where you can only drill ONE hole to effective depth instead of two or even three, what does the extra couple tenths actually DO for you?
So while NO, I won't be taking along a Walther PPK full of ball ammo to Alaska for my final defense against Kodiak bears, I no longer regard the concept as suicidally insane as I would have 30 years ago.