It sucks that this guy was killed, but his death was completely preventable, and a consequence of his arrogance and hubris. The people of North Sentinel Island are completely isolated from the rest of the world, by choice. They've never been exposed to the diseases of the world, and they don't tolerate visitors to their land. This guy put the entire tribe at risk of death, just so he could proselytize and impose his religion on them. His death was an act of self-defense.

https://www.mirror.co.uk/news/us-news/man-killed-uncontacted-tribe-after-30620890