For legal reasons, there'd just have to be a clear procedure where parents would take or refuse the decision, probably after being informed of the baby's overall condition and potential in the presence of a witness. I can't imagine how it could be realistically practiced without one.

Humans are pretty ok with making cold decisions in the abstract that they could never carry out themselves due to physical revulsion and/or emotional trauma.

The number of people that would sign a death order is greater than the number of people that would kill someone else personally.

Potential for tension and cognitive dissonance. Few things in our culture are censored this way, not even executions and torture.

Does society feel conflicted bothered that child pornography is censored? We can even extend existing child pornography laws with a few good judicial decisions to cover this.

Would feel unusually hypocritical.

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