Lots of breakthroughs in medicine happen without editing genes?
Why would the presence of breakthroughs in medicine on other fronts mean that we shouldn't try gene editing?
what happens when we get to the point where we need to use the scientific method to test if the gene editing was successful and didn't cause negative outcomes for the child's entire existence perhaps?
That is what clinical trials do today for medicine. Are you opposed to those as well? Many have died and many have been saved in the pursuit of better care.