Changing the damage of his hook rather than his bullets doesn’t make it significantly easier though, you still have to land the hook and a well placed shot plus melee. It reduces the chance that an enemy survives because of shotgun spread RNG and which character they’re playing, which is out of my control as the Hog player.
If you’re planning out your positioning and hook a key target like Lucio then he shouldn’t survive because Hog’s damage is inconsistent against some targets. When in the same situation you could hook a Doomfist and guarantee the kill when he has more health but a larger hitbox.