Maid they gave the reasons on the programme why they decided against PGD. I don't think its up to strangers to judge their decisions unless it is patently obviously seriously detrimental to the child
Treacher Collins can be seriously detrimental and disabling to the child. Devastatingly so. For me, it has always been the most emotionally difficult craniofacial disorder to process.
It's very tough to see "mild" cases (as this family present) and argue against "It's not unreasonable/cruel". The problem comes with how variable it can manifest within families - a mildly-affected parent can have a severely-affected child. Even mildly-affected people have multiple, extensive operations ahead of them. Severely-affected patients, if they survive, have such disabilities that are so utterly heart-rending to read about that I can't help but wonder why people wouldn't pre-screen.