FR lore guy here.
Yes, guns exist in FR and have existed since 2E FR Adventures handbook. They don’t call it gunpowder, though, they call it smoke powder and it is considered magical. The guns listed in that handbook are early firearms, such as arquebus, blunderbuss, and match lock type of guns.
/stands on a soapbox
FR has a very weird history with technology. They have a deity of technology, Gond, but then somehow Mystra (goddess of magic) was able to restrict certain tech and make it not function, i.e. smoke powder instead of gunpowder.
One of the things that LOVE about BG3 from a lore perspective is that it shows these huge ruins that existed in the past, which is said to be better than current times. This is one of those many layered things due to how old FR is and how much RPGs have evolved in the decades. FR existed in the 60s when Ed was a kid, he wrote about it in Dragon magazine in the 70s and 80s, and then it released as a world in '87. Due to that, the lore and the mechanics haven’t matched up well. The sourcebooks talk about how Netheril was the most advanced but they don’t show that well. Or, the sourcebooks that come out don’t reflect it well. Or they created brand new classes that no longer exist to show how much better the Netherese spell casters were.
(If you want a good example of a world that shows this, but has horrendous mechanics, check out Exalted.)
It’s why I like PF1 because it has classes that fit and could be used to show what the casters were like back then. I tried to do a campaign that only had core PHB classes and the idea was to have the PCs find the way that old kingdoms used to do it, bringing those things back. It didn’t work as my players didn’t like to be restricted but I still like the idea of it.
(To get really geeky, my idea was that if someone wanted to be a Magus, they play a multi class fighter wizard and then at some point, they would find the old records of a Magus and could freely convert all levels over to it. Arcanist was going to be the Netherese Wizard. Things like that. It didn’t work out.)
/gets off the soapbox
I have hit the lever several times and the platform hasn’t gone back up so I guess I teleport.
Thanks for the discussion!