In my head canon the Jaffa were used as more of a source of projecting power and fear but not so much being used to wage war in the sense that we wage war. They aren't actually trying to win a war by military tactics, it's more of a distraction from boredom since they're thousands of years old.

Something like the Goa'uld is playing high stakes chess and have to play by their own rules, while SG1 doesn't play by their preset rules and plays to win.

Iirc don't goa'uld have a tendency of stealing technology. So I would assume they just never found technology that did that. I don't even think they had scientists or people who learn to make new technology for the Jaffa. So I would assume it just never was found.

Plus earths technology is way different because of our smarts. Jaffa never got that ability as they are slaves to the goa'uld who think there ways are the only ways.

goa'uld are paranoid creatures right? Maybe makes the possibility of coordinated uprising/betrayal too high.

My assumption is the society doesn't encourage down to up communication. The leader says take that point from the east, so they take it from the east. Saying the south us a better option might be seen as defying the gods.

I also recall in s7e01 the Jaffa did have a way of receiving ordered, but no way to talk back which is where my head canon comes from.

The teleballs , as I call them, seem like a 1:1 system not a one to many like you would need for large group tactics.

They have horns