The main advantage of early guns wasn't that they were more powerful, it's that they were easy to use. You can train someone to fire a gun in a day, while it takes months of training just to get an archer strong enough to draw a bow.

Also the whole "the Europeans were dirty diseased peasants" thing isn't accurate, and I have to say that IMO the right response to racist depictions of indigenous people as unwashed savages isn't to just turn around and say "actually the stereotypes are correct it's just that it's about the Europeans this time".

And Indigenous people had more advanced technoglogy than many give them credit for but "The Europeans were technologically behind indigenous people in nearly every way. " is just blatantly wrong.

I do think you're right though that without smallpox and other diseases the Europeans wouldn't have colonised the Americas, though there were several other major factors in it.

P.S. I'm not a historian, grain of salt, etc.