We should remember the possible arm race of magic & firearms in a fantasy world. Players would try new tricks against gunpowder. For example illusory magic to create effects like smoke-grenades or decoys. Throwing stones with magic runes to summon planar swarms monsters. Creation of ectoplasm to block canons or "water gunpowder". Teletransportation a burning match toward the explosives warehouse.
Conan or Tarzan can't face Flash Gordon or Buck Rogers with a laser ray gun.
In a fantasy world some taboos could forbid the firearms, or the war deities could bless melee warriors with bulletproof defense magic. Gunslingers couldn't enter the Valhalla because firearms are fight "without honor". Or killers with guns could be cursed with victims returning as ghosts to haunt their killers. Firearms (without special permission) couldn't work in urban zones caused by a magic area effect. And adivination magic would allow to know when and when a firearm was used, by who and against who.
Other point is firearms are forbidden, but magic wands with no-lethal damage could be allowed.
Deities with the gift of prophecy to know the future could know when gunslingers from other world arrived, and a found firearm could be studied for reverse engineering.
Dragons, giants, wizard guilds and other beings wouldn't wellcome the firearms because thanks these simple recruit with a short training time could be enough to kill powerful enemies.
In the dungeons the firearms are too noisy.
Biopunk technology could allow "guns", crossbows that reload itself thanks artificial muscles.
Maybe constructs are too expensive to be used in a battlefield, but a magic motor in a war charriot could mean the end of the chavalry.
* You haven't thought about that, but the simple toiler-trap or trapway in a toiler seat could be a revolution, because the latrines had to be far or outdoor caused by the bad smell. (the water in the toiler-trap blocks the gases and bad smell from the sewers). The isekai mangas don't tell this.
