The thought never crossed my mind for SG-1 sets, but now I really want them. Lol
Considering that Man of Steel and Indiana Jones sets had real-life based military personal in uniform with weapons, even military vehicles, I don't see why SG-1 would be an issue.
As Faefrost said, they could cobble together some adequate Jaffa (and other species too, tbh) weapons using Ninjago parts. All the set would really need are minifigure prints. I just didn't think SG-1 was that well-known, especially to make a LEGO set, but I guess we have a Queer Eye set so anything is possible these days.