9mm is not a con. Its older than the .45 by a few years, and despite being on the losing end of 2 world wars, has displaced .45acp, .38spl, .40s&w, 10mm, .357sig, and .45gap amongst others in the hands of serious users is seriously impressive.
There's very little difference between service calibers ballistics wise
But there's a big difference between them capacity, and cost per round wise, and 9mm beats them all there
Little difference in 230 grains moving 850-1000 fps and 115 grains moving 1100 fps? I don't think so.