It was a the death of 90% of the population to small pox within one generation that allowed colonization. The Europeans were dirty and diseased, untrained peasants. Their firearms at that time were inaccurate single shot rifles, that took minutes to reload. Analysis of indigenous bow techniques showed the common capability to accurately shoot multiple arrows in rapid succession.

And it goes beyond war: Indigenous people didn't farm as Europeans did, we instead cultivated forests with eidble plant species that complimented each other to kept the soil healthy. The forests across the Americas were thousands of years into a cycle of land management that kept grown food naturally abundant and plentiful, without having to clear the land. Indigenous peoples were expert and managing the population of the animals of their areas as well. We understood which members of an animal population should be hunted, and which should be kept for the health of the species. We then knew how to fully utilize every part of the animals hunted. The core of most indigenous cultures rotated around ethical and efficient management of the land's resources. What did the Europeans do? Accidentally gave an entire continent a super virus, then stripped the forests clear to plant shitty crops not made for this climate, and hunted countless animal species to extinction. Europeans were not technologically advanced at all. They were just diseased. That's it.

Rest assured that without smallpox, the Americas would not have been colonized. Population density and technological differences would have made it too dangerous and expensive an undertaking.

The native tribes mostly did have gunpowder by that point, they were very motivated to trade for rifles and ammunition and the US government sold them rifles and ammunition through the Indian Agency.