Who knows far in the future, but for now you could only do it to a test tube zygote and finding one has extra chromosome it's easier and safer to just use another. We're far from having any practical use from this technology.
Ethically speaking, I don't think there's an eugenics problem because we're talking about removing extra copy, with the same genes still remaining.
Though I don't know if if it's always 100% identical chromosome? I imagine there'd have to be some theoretical chance of mutation, but that'd still 99.999... Except that would kind of make it eugenics problem same as removing a single gene, but still in lesser sense.







