The reason is that genetics/evolution don't yet seem to fully explain how humans exist. A computer genetic algorithm run for a billion generations doesn't lead to anything anywhere near the the complexity of a human.
I suspect there are as-yet undiscovered effects which shape the next generation. Whether that be DNA methylation, gut bacteria passing from mother to child, selection of the 'correct' egg or sperm out of millions, or something new and un-discovered etc.
And if those effects are bypassed with artificial conception, we might end up with humans which aren't as strong, aren't as smart, aren't as well adapted to a changing environment, etc.
The effect will be small for each generation, but after 5-10 generations of a combination of artificial and natural conception you could end up with meaningful loss of fitness - or perhaps a lack of gain of fitness that would have otherwise occurred.
Yes, if we end up in some corner-case dystopia where evolution and natural selection continue to be in charge of fitness. But evolution and natural selection bring much suffering to the unlucky. In other words, if you go to a hospital, you'll quickly learn there's far more human suffering caused by God and Nature than by the "cruelty of man". Though common sense is never assured victory, I look forward to a world where our children live healthier and longer lives due to us properly messing with God and Nature.
You'd have a rather different opinion if you had to squeeze out a water melon out of your genitals.
It's like arguing with someone who doesn't believe in using seat belts when driving. "Why should I put them on?" they say, and when you try to explain what might go wrong they won't listen to any explanation that isn't a hyper-concrete hypothetical. So finally you give in and say, "Well, when we get onto the highway, a truck might lose control and hit us", and their response is "I don't think that's very likely, it seems highly improbable that today we will be hit by a truck when getting on the highway".
I agree with OP that this seems like the kind of thing where the unknown unknowns are so great that the correct approach is serious caution, and that any demand to know exactly how or why it will go wrong, falls in the trap where every specific example is very unlikely to be the thing that goes wrong, but still in total there's like an 80% chance that it goes horribly wrong. I don't know if we have the terminology to talk about this kind of failure mode. "You shouldn't play God" maybe? At least you shouldn't ask for specific examples of how things could go wrong, if you're going to turn around and claim each one highly improbable.
Like it seems horrible not to help the individual, when we have the technology to; but it's also horrible to hurt your species by selfishly propagating faulty genes. And this seems like the kind of problem cultural taboos are good at solving, and I don't really see any other mechanism by which a species can avoid this filter trap.
Humans could easily be successful with a similar model, and did so in the past before fertility treatments.
Societies functioned in the past while taking away some rights from its citizens (like ownership) but nothing as fundamental as only a few able to reproduce.
I didn't have "creationism" as the top answer to a HN post in 2026, yet here we are...
How do you know it? Sci-fi tropes are not a good argument.
Can we stop adding unnecessary JS to website to stop global warming by calculating AND ALTERING SCROLL?
Firefox on Samsung S23, not exactly a new or a powerful phone but rendered it fine.
That being said, the scroll was as smooth as regular webpage scrolls. Usually these JS scrolls aren't able to avoid dropping frames or otherwise introducing judder, but this one does appear to run at a consistent and high framerate, which is technically impressive.
Because it is unlikely that you just punched a hole through the plan of the several dozen people in bioengineering, life sciences, and other related fields that are at this company.
Shinya Yamanaka created iPSPs in 2009:
https://en.wikipedia.org/wiki/Shinya_Yamanaka
Guess the japanese excel at micromanaging. Although one could say that the research here in the article is more epic than Shinya's discovery, but I remember having watched one of his presentation and it convinced me of pure epicness, if you understand how his team found the "Yamanaka factors". That was by human (work) consistency. About as epic as Christiane Nüsslein-Volhard and her mutant screens, that also involved tons of micro-experiments.