The world is always changing, cultures come and go, life styles come and go, people come and go. Part of life is accepting the change. It's the only way to truly find sustained happiness. That said, I think some stuff's worth fighting for.
There are plenty of questions when it comes to genetics. Theoretically we'll be able to do a lot more than guarantee people won't be born with genetic variants that allow for "disabilities" or diseases.
We'll be able to take a normal hearing person and manipulate a few genes and give them super hearing. Give a normal sighted person the ability to see better than any natural born. We'll be able to artificially increase the average IQ to that of Einstein and Hawking or more...
Is any of it ethical? Is it going to produce more good than bad? Who knows... But more kids aren't going to be given the choice once this stuff is possible. There's plenty we have choice in though, is this different?
The only constant in this world is change. We only get a glimpse of it all in with short lives (maybe they won't be so short in the future though).