This is so one-sided it isn't funny. Any time one of these scenarios come up, the only way it even comes close is if (a) the side with advanced weapons are complete morons and (b) the side with the primitive weapons are uber-competent and don't suffer any demoralizing effects from seeing their buddies get their heads blown apart by some force that can't even be seen and they have never experienced before.
First, the scenario: the attackers are not going to simply land within sight of the village. That's just stupid. For a kidnapping mission, the chopper is going to land some distance away, out of sight and sound, and the team is going to approaching on foot, at night. With night vision and IR gear, they have a total advantage over anyone who happens to be on guard in the darkness. Throw in a couple of small drones with similar sensor systems on overwatch, and they'll know if anyone is hanging around. This gives them the opportunity to go where they want to with very minimal chance of discovery.
What happens next depends on the mission goals: are they wanting to catch as many people as possible and not worried about causing as many fatalities as necessary? Well, that depends on the tribe, which some observations will tell you. If it's your standard tribal society, the leaders in a threat situation are either going to be the eldest, and minimal physical threat, or they are going to be the strongest/best fighters and thus tending to lead from the front.
So you prep a killing ground. Three snipers in elevated, concealed positions. One handling drone surveillance, and possibly remote detonation of mines they've placed in advance just in case a retreat is necessary. The remaining two then lure the tribal fighters into the killing ground by doing something that looks threatening, but not too threatening. What you want to do it make the leaders of the tribe become apparent, and they will be. And then long before they get within spear range, the snipers start taking them out. Hell, at under 100 meters or so, which is well beyond spear range but short range for a rifle, they don't even need sniper rifles. Trained shooters, firing single shots, at a distance of 100 to 150 meters, should each be able to hit at least ten targets per minute.
Now, the immediate counter-argument is that, sure, but the tribespeople will be looking for cover, they're not just going to stand there in the open. I wouldn't. You wouldn't. But the difference is, we know about firearms, even if you've never touched one in your life. When a primitive tribe starts seeing people going down with no idea what the hell just happened, the majority are going to freeze. And you take out the leaders. They'll be the ones in front who were looking all threatening before their skulls started exploding.
With the leadership gone, people will be cowed. The attackers might be required to shoot one or two to make the point about resisting, but most of the tribe will simply be too frightened to do anything. Then you march them to a someplace you've previously secured (more remote-detonated mines for protection) out of spear range from any concealment in case some idiot who managed to get away got brave and tries to come back) and then you call in the helicopter.
That's an attack by people with advanced weapons who aren't morons.
Now, if you want minimal casualties and are content with low numbers of captives, initially the same. Infiltrate, surveillance, and then you do snatch missions. Again, the attackers have the advantage in knowing where people are and being able to see where and when the tribe can't. Watch to see where individuals go alone, and grab them, and take them back to your secure location. Keep doing it until the tribe notices people are missing, and quietly slip away calling for the chopper. No fuss, no muss.
Advanced weapons, sensors, communications, and training. This is no contest.
Now, on the other hand, if the attackers do operate like morons and the tribal defenders are stone-age ninjas completely unphased by the utterly Out of Context Problem they've suddenly found themselves in, then sure, go Stormtrooper vs Ewok all you want.