Some of the happiest children you see have Downs.
If it was a question of them actually eradicating the Downs then wonderful, but it's not, it's more a question of terminating the babies with it.
I had an uncle that was a r..word (the medical terminology when he was born),
He obviously wasn't capable of filling forms out or looking after himself independently but he led a happy enough life.
It's up to the individual to weigh up what they are willing to sacrifice in time and effort against the love they will be given in return I suppose.