Actually this is another good counterexample! As I recall, Incas lost battles against the Spaniards where they had something like 100x the numbers. It's true that they were initially divided, but they quickly united against the Spanish--and it didn't really help. The technological advantage was insurmountable.
How could it have been? It wasn’t like they had machine guns. In best case I believe it takes something like a full minute to reload a musket. Zerg rush would be sufficient tactics. 100 yard dash means your hoard of unarmed natives is through the musket range in maybe 10-15 seconds and pulling limbs off the spaniards already.
Why this wasn’t done is I think the big mystery and lends credence to the idea of spaniards having significant force numbers through allies.
Don't forget horses, armor, and steel weapons. It seems like Incan weapons had a lot of trouble penetrating Spanish armor, while the reverse was not true. Also, the Incas didn't just lack cavalry; they lacked the weapons and tactics to counter cavalry (such as pike formations.)
That said, I was thinking of the Battle of Cajamarca, which was actually a Spanish ambush. 100x was probably overstating it; under other circumstances (e.g. rough terrain) Spanish technology had less of an edge.
You don’t have to penetrate the armor with such a manpower advantage. Just throw four or ten people on each spaniard and rip them limb for limb. Don’t need to penetrate any armor. Can just take it off or stab sticks in between the plates. Conquistadors were not fully armored either.
Turns out I misremembered. Incas never fully united, and even though Spaniards had a huge technological advantage in some battles, the war as a whole was more evenly matched. Technology, disease, and infighting ALL played a part in their victory.
