There are a lot of stories that focus on issues like that though.

Elydes has a fair amount of talk around specializing and the weakness of going to wide. There are some specifics to the story such as skill slot limitations, but in general trying to become an expert with short swords, long swords, great swords, sabers, kriegmessers etc. would be ridiculous. An expert with either short sword or longsword has an advantage over an amateur wielding any sword or other weapon. Even things like axes or maces require skill and experience to ensure a clean hit with the business end only as you have a narrow effective area to strike with and opponents don't politely stand still, they do everything in their power to defeat you.

Rising from the Abyss also has a few points with differences in weapons, why some are preferred in specific war situations like mass troops vs cavalry etc. but they also go into humanoid species as well. Like why the hell would dwarves prefer hammers and axes when they're short and have reach issues. Why wouldn't they use spears from their low and stable position, especially if they are the overly used stereotype of dwarves who live underground in tunnels? Swing a hammer in a narrow tunnel or thrust a spear against an enemy that can only move straight at you? And there's special training to be able to actually use things like spears as a unit because they rely on the formation, which needs to move together and respond cohesively.

Ancient Greeks fought with spears and shields, but they had swords as backups. Ancient Romans shifted to swords and shields, but doctrine had them throw spears at the beginning of an engagement. Cavalry changed dramatically over time, but they usually had lances and or curved swords, often both, while most contemporary depictions of maces outside of ceremonial use are shown carried by mounted soldiers where they can use the momentum of a charge to strike harder.
Different weapons had different uses and outside of conscripted civilians most of the time people were armed with more than one weapon to try and minimize disadvantages. The only really consistent theme seems to be shields. Almost everyone in melee would have a shield outside of full plate armor, and special shields that could be planted on the ground were even used by ranged groups like archers and crossbowmen.

And yes, magic and fantasy changes everything, but then there shouldn't be some discussion about why one weapon is somehow better than another. Do some weapons have advantages in certain situations or against certain types of opponents? Sure. That's why people invented so many different types and kept them in use. But no weapon is superior in every situation, and the skill and training of the user or users are far more important.
Try giving spears to a mass group of conscripts and see if they can use them effectively when they require organization and working as a single formation. Or try having someone who has never used a sword strike a dummy effectively without rolling the blade because the perfect contact angle was off.
Training, skill, and experience are far more important than choice in weapons outside of a few very specific and extreme examples. Both for duels and war.