Imagine if humans one day become so technologically advanced in biological engineering, that each and every baby born will be born with desirable genetic features. Anomalies in genetics that we know causes immense life-long suffering - such as down's syndrome, Kleinefelter's syndrome or missing limbs would be eliminated through the controlled environment of the lab in which defective embryos would be weeded out and healthy embryos can develop in optimal conditions. These embryos would develop into humans who will not have to go through the pain of living a disabled life, where they are treated like outcasts in society. This would solve problems to do with terrorism, wars, rivalry, tribalism, social shaming. These are all because of physical differences between individuals.
If Biological Fascism was implemented, there would be a lot less suffering in human society. Why would anybody be against that?