No government is truly pro-immigration (open borders).

Failed states dont want the exodus and subsequent loss of power due to skilled people no longer paying taxes to them.

More prosperous states fear the loss of power from new people who haven't been trained by the system (schooling etc).

Either way, it's the people themselves who lose out. Those trapped by authoritarians, and those who'd benefit from more productive young people in their economy. Governments care about themselves, not their people.