I found this episode of The Ready Room made me feel less good about the main episode. For example, at the end they're recapping why eugenics is banned in the Federation, and they say it's because of "potentially violent impulses". But in Doctor Bashir, I Presume it's established that it is not just because of the eugenics wars, but because if you allow genetic augmentation it creates a medical arms race where parents feel compelled to genetically augment their children to keep up. Is that being retconned or was just it just a badly written summary? We really don't need Star Trek to be making the case for eugenics, you guys...
"Doctor Bashir, I Presume" makes the case that augments can be unstable and dangerous.
Two hundred years ago we tried to improve the species through DNA resequencing, and what did we get for our trouble? The Eugenics Wars. For every Julian Bashir that can be created, there's a Khan Singh waiting in the wings. A superhuman whose ambition and thirst for power have been enhanced along with his intellect. The law against genetic engineering provides a firewall against such men, and it's my job to keep that firewall intact.
It's safe to say that the attitudes toward genetic modification will shift and morph over time. In the TOS era, violent conflicts with augments are much more recent history, so it makes sense that that's the first justification that comes into play in these discussions.