Earth is the Federation's homeworld, and if it's still on the books there, it would carry over. Up until SNW, it was more a case that Human augmentation was banned within the Federation, because the Federation did have facilities like the Darwin Station (seen in TNG's "Unnatural Selection") that actually specialized in genetics research. So the Federation was still pursuing a form of genetic engineering, but mainly to fight various diseases rather than create a new race of superhumans.It's not just Earth that's banned it. It's the Federation.
This strains credulity, in addition to being inhumane on its face.
Unfortunately, Darwin Station also makes a case why messing around with genetics can lead to accidents, but nevertheless, the Federation still had the facility in spite of the ban.
I think that goes back to the idea that the Eugenics Wars was something Humanity never wants to even come close to again.I mean, we don't need an answer because eugenics has a horrifying history on Earth in RL.
The Federation is found on ideology not practicality and the ideology is not that transhumanism is impractical, it is transhumanism is EVIL.
The downside of being in an "enlightened society."Which I think fans need to think about when they wonder why so many Federation folk react with visceral disgust.