Honestly, I really can understand both the plight of Bashir's parents, but also for the need to keep genetic manipulation of humans on a tight leash.
I'm in a rare but probably not unique position here; I work with special needs kids, but I was special needs myself. My social impairment is significant enough that it has hamstrung me in aspects of life most people consider stsndard: no IRL friendships, no career, no romance, no possibility of marriage or children. I have a pretty good idea of the challenges ahead for many if not most of my kids, and let me tell you, if there was a way I could delete the autism or whatever other issue they have to deal with, at the mere cost of subtracting two years from my life... I would take that trade. I'd take it for more than one of them if I could.
But then, we have the dilemma... while I'm sure that severe physical and mental conditions can lawfully be cured via genetic tweaks (the EMH had no ethical issues with fixing Miral's spine), where does the line get drawn? Jules Bashir has a learning disability, does it cross the line to fix that? Or a speech impediment, or severe myopia, or a cleft palette? Once we let the genie out of the bottle, it gets harder and harder to stop, until finally genetically designed humans become the standard, rather than the "break glass in emergency" solution for the worst case scenario.