Pondering with rising wet bulb temperatures globally, whether Darwin will kick in and whether humans will evolve into a more heat resilient species. Natives in Nepal are adapted to lower oxygen, so why shouldn't that be possible?
It would require conditions where those who are better adapted to higher temperature produce more offspring than those who aren't, consistently over many generations. The Nepalese would have developed this change over thousands, if not tens of thousand of years. The climate crisis is likely to come to a burning head in the next hundred. In all likelihood, we'll use technology to circumnavigate the issue and it will never get to the point where humans are put into a position where adaptation occurs.
Evolution "cares" about one and only one thing - spreading of relevant genes. Technological advances means there's almost no difference in terms of procreation between more and less heat tolerant people.
