The fundamental problem with Eugenics is that the more fit for a specific niche you become, the more vulnerable you are to niche collapse. For example, if someone was genetically optimized to be the perfect software engineer, and now AI had made their job redundant, and the rest of their skills were mediocre at best, they now are not fit for anything else. We see this in nature all the time where a species becomes so hyper-specialized at one thing, the second there’s a shift in the environment they are instantly past-tense.

Diversity lacks efficiency, but it improves resilience. Another example, if you over-engineer the drive shaft on a truck to very precisely meet the expected load limit and no more to save weight, the second you encounter a situation that overloads the drive shaft it will snap like a twig. The added weight of safety tolerances is inefficient… but it is also the only way to approach a world far too complex for you to anticipate every possible variable.

For an example of how this works in human biology, lets say you found a way to completely eliminate sickle-cell anemia. That’s great, people will live much more healthy lives right? Except the second you do that, millions of people that you cured instantly start keeling over dead. Why? Because the sickle-cell was protecting them from malaria, and while it wasn’t a great solution, far fewer died from sickle-cell than would have from unchecked malaria.

Engineering is always limited by how many of the real world variables you actually know about. It’s the unknown unknowns that will sink your titanic every time. This scattershot, random evolutionary system that produces us? Yeah, there’s a reason nature works that way. It’s actually the most efficient way to keep surfacing variables you didn’t yet know existed. For a lot of really complicated reasons, it’s actually impossible for you to think of everything when trying to engineer the perfect human, and a surprising number of things you can’t figure out a reason for and assume they’re useless at best or a harmful waste at worst, turn out to be the one thing that saves you when everyone else is dropping like flies to a thing you didn’t even know could happen yesterday.