You have to factor in Eorzean (Lominsan) manufacture versus Garlean manufacture. Then you have to factor in how gunblades are supposedly inherently superior courtesy of association with the big bads. Then you have to factor in magic aether, which throws everything out of whack.
tl;dr: I think the comic book rule of superhero competency applies here. Guns are as effective as they need to be.
tl;dr: I think the comic book rule of superhero competency applies here. Guns are as effective as they need to be.