Creating a special nation for specific people means displacing other people, like what the Zionists are doing to the Palestinians.
That is not a practical solution because it means bloody conflict for the next 200 years.
Nation building is hard, risky, bloody and you can't start a nation on the basis of an identity. I think national identities form as a result of nation states. You can't start with an identity and build a state around it. You have cause and effect confused. The Zionists didn't base Israel on a Jewish national identity, they based it on the fact that the British empire wanted a foothold in the middle east and needed people to operate it.
If eugenics is threatening to make a comeback it would be easier to just slaughter the eugenicists. Erase the Erasers. Stop the cycle of bloodshed at the source, before it even begins.