One of the recent laws in Trek that gets looked at a bit, is the genetic engineering ban within the Federation. It appears to have been passed as a direct result of Earth's Eugenics Wars, to prevent a repeat, and seems to have been grandfathered into Federation law, owing to the hand Earth had in its creation.
But we also see that doing so came with major downsides. The pre-24th century version of the law applied a complete ban on any genetic modification of any kind, and a good faith attempt to keep to that resulted in the complete extinction of the Illyrians.
In Enterprise, Phlox specifically attributes the whole issue with the Eugenics Wars to humans going overboard with the idea of genetic engineering, as they are wont to do, trying to improve/perfect the human species, rather than using it for the more sensible goal of eliminating/curing genetic diseases.
Strange New Worlds raises the question of whether it was right for Earth to enshrine their own disasters with genetic engineering in Federation law like that, particularly given that a fair few aliens didn't have a problematic history with genetic engineering, and some, like the Illyrians, and the Denobulans, used it rather liberally, to no ill-effects.
At the same time, people being augmented with vast powers in Trek seems to inevitably go poorly. Gary Mitchell, Khan Noonien-Singh, and Charlie X all became megalomaniacs because of the vast amount of power that they were able to access, although both Gary and Charlie received their powers through external intervention, and it is unclear whether Khan was the exception to the rule, having been born with that power, and knowing how to use it properly. Similarly, the Klingon attempt at replicating the human augment programme was infamous, resulting in the loss of their famous forehead ridges, and threatening the species with extinction.
Was the Federation right to implement Earth's ban on genetic engineering, or is it an issue that seems mostly human/earth-centric, and them impressing the results of their mistakes on the Federation itself?
Personally, I'd argue that it wasn't the correct decision. Banning technology wholesale doesn't really do anything other than create a black market for that technology. Bashir and Una are both genetically engineered but had to go through some extremely sketchy circumstances due to it. There was always a chance that it would have gone poorly for both of them. Bashir from modifications done that don't work and Una from just outright being imprisoned, exiled, or potentially killed by people who harbor hatred for those who are genetically engineered. With the blackmarket modifications come blackmarket consequences. People who can't control themselves and only give more credence to the people in-universe who say that genetic engineering is abhorrent.
So much good could be done with genetic engineering but the focus is only ever given to all the negatives that have come about from it. Vulcans should logically see this, at the very least, but there was seemingly no pushback inside of the Federation over it. My assumption (in universe) is that the humans forced the subject. It was too soon after the Eugenics Wars for Humanity to even consider the idea of genetic modification being used for anything. It was way too sensitive. I can honestly see it becoming a potential deal-breaker for Earth as well. Considering the benefits that came from co-operation, foregoing genetic engineering probably just seemed like a worthy trade off.
Bashir is also an example of people who did go overboard on the idea, with his parents deciding to give him that extra bump into solidly superhuman territory, rather than just enough to put him at "typical human". Although from Mirror Bashir, there's a chance that genetic engineering was never needed to begin with, and he would have grown out of his learning disability, given time and support to do so.
That would make some logical sense, since Earth was the main power bringing everyone else into the Federation, risking angering them, or having them decide not to form the Federation at all might be too great, seeing as it was a long-sought chance for peace. From what we also see, none of the other founders had much of a history with genetic engineering at all, so might not have been an issue for them either way.
For the Vulcans, there might have been a small advantage in humans deliberately stunting their technological development in some areas, both considering their history, and that the Vulcans had been concerned that human technology was developing much faster than their society/culture was, enough that they were trying to slow humans down some (to not much success).
I was a bit unclear when I pointed to Bashir. I meant that genetic engineering wouldn't lead to evil, not that his circumstances weren't created by overzealous parents. My apologies on that front, that's totally on me.
That's actually a very good point. I've been meaning to rewatch Enterprise but I have a vague recollection of the Vulcans not being always that happy with how the Humans did things. Then we had the extremists that we saw in Discovery who outright bombed certain areas and tried to assassinate Sarek, all because Vulcan above all else. Those extremists had support too. That must have come from somewhere. Why not have them come from, or at least be around, during the founding of the Federation? You really do make a great point. Never thought about that!
TNG also had Vulcan extremists (trying to recover ancient psyonic weapons) and Sela must have expected a fifth column ready to defect once her thousand troops landed and gave them an excuse.