I have friends who are not having children despite wanting them because of a genetic defect. That is eugenics, and most would consider it the ethical choice for them.
Perhaps, but as time progresses such methods meet more resistance/grey areas. For instance there are gene sequences that have strong correlation with intelligence, and taking the same schema to avoid having a (nearly assured) kid of low intelligence would be more controversial obviously, or well similar cases 100 years ago of rapists and scum of the earth looking to have kids yes? Look not debating eugenics here, just pointing to any mass involvement of Crispr on child-rearing will meet to the same fate I am sure.