>I suppose this also relies on national productivity being the product of, not the sum of individuals​ productivity.

By that logic you can easily argue it's imperative to weed out those with productivity close to 0 (and below 1).

Great people inspire greatness, awfully people can bring their whole environment down. That's why ghettos are such a bad idea.

From your arguments alone I wouldn't be able to tell which side you are arguing for.