It’s not clear that people in developed nations currently live in the “real world”, or that evolutionary adaptations that optimize for getting the maximum number of people in “under-developed” societies to successfully reproduce and grow the next generation to reproduction age are also optimal for our current goals of staying active and comfortable later in life.

Like I’m definitely not saying you’re wrong - there’s a good chance you’ve hit the nail on the head even. But just noting that it’s not axiomatic in today’s environment.

One note is that today humans would be better off without an appendix because we live densely enough that we no longer need a super-secure vault to store gut biome for solo gut repopulation. That was useful when we lived in small tribes where every single person might get dysentery at the same time and no one would be left with a healthy gut biome to share with others. But New Yorkers certainly share all their gut biome with eachother on a daily basis, so the appendix now only contributes appendicitis to our population.