It would only justify genocide if the foreign population were expected to commit a much larger genocide.

It would imply that people are not created equal (in a human rights context) and in particular do not deserve equal treatment.

Nonsense. It would imply that equal treatment would not result in equal outcomes.

Equal treatment: rapists go to jail, regardless of their country of origin.

Unequal outcomes: 10 in 100 people in Rapistan are in jail, whereas only 1 in 100 people in the Withpermissiononlyville are in jail.