Thank you for your time and effort to explain this.
Well, honestly, this smells national socialism from a mile.
Which genes are bad? Is it really that genes are bad? What about their mutations?
I have (not really suffer) ehlers-danlos type 2. Which is genetic disorder. Some people with it - like me - are lucky and have it really benign. It doesn't really affect my life in any way. It doesn't affect lifespan in my case. Then there are some others - with exact same gene mutations - who suffer constant pain to the point they would like to die (literally). Not to mention constant medical emergencies.
Now, I have almost no problems because of eds. And one benefit - apparently I have lower risk of colon cancer. (there is more bile in the system which is laxative which helps preventing colon cancer, plus the colon is built differently, in my case causing "stuff" to move quicker). So, how would you know my gene mutation is good or bad?
And how do you know that if you change it, something else won't be totally messed up instead? There is always the problem of unintended consequences.
Not to mention that once you would open this pandora box, you'd also need to deal with prospect parents demanding "gene therapy" for their future kid because of a gene they think is bad. Like with cosmetic surgeries. People with gene A have higher risk of being short, so please doctor, please, let's "fix" that. Our boy can't be short! Can't have red hair! Can't have 40% higher risk of being depressed or obese too.
And here we go, all blond, tall, beautiful.
Wouldn't you agree?