If you’re a fan of the idea, you’re either a nazi or really really ignorant/naive/misinformed.
So I’ll assume the latter and try to briefly explain to you why it’s so bad: people bad, authoritarianism inevitable, results in ‘oops you’re not “human” because you lack/have X, you must die’
Humanity, just like nature, thrives with diversity. Eugenics starts with “getting rid of nasty diseases” but it’s always 1 bad classification of “disease” away from genocide.
Ok then lets say you could prevent your son from have cancer in his teens or heart disease in his twenties or addictition in his forties or alzheimers or dementia or any other type of disease it's not you conforming to society like changing looks or anything. But if done correctly tell me you would not want your son to get the best start from birth?
Scientifically probably not. But lets say in the next 5 years we can pinpoint diseases that were terminal. Counting out the government or anyone else besides loved ones or at least just the parents?
No not the government because it is dumb as hell but if parents had the option to have a gurantee their child will outlive them then it should be up to them and them alone.