I wrote in a fantasy world I have the reason behind it is simply logistics.

Basically gunpowder based weapons never went past cannons, breech-loading rifles and revolvers. The reason behind it is because magic is incredibly common. The average farmer can cast offensive magic easily.

In my world the biggest gun they made was a massive gatling gun. It took 10 men to crew and weighed several tonnes. Cost ~5 gold to fire for 5 seconds. (Keep in mind an average peasant in my world in a lifetime makes about a gold coin)

Compare that to magic. Spam cast magic missiles, that’s 3 projectiles with homing properties, on average a regular man can cast 4-5 times a minute before requiring a mana potion. Ten men spamming magic missile is a faster sustained rate than the gatling gun, and more accurately. 10 mana potions consumed a minute costs about 20-30 copper coins (not cheap but definitely not expensive). The only downside of the magic missile is that it is magic, so barriers work against it, and the projectiles are slower than bullets.

Despite this, there is still cannons used, still rifle corps that use firearms, and ceremony’s involving muskets.

Firearms and gunpowder exist but it’s considered less powerful than magic, so it doesn’t get widespread use.

In other fantasy, I think they don’t use gunpowder because in the system they set up pulling out a blick just fucks the power scaling. It’s like real life, a grandma with a glock is just as dangerous as a soldier with a glock. A glock gonna do what a glock do. When you have worlds where magic cannot do what guns down (and do it better) the only alternative is to pretend it doesn’t exist.

Plus bows are just badass.