Emigration restrictions are something that should be avoided if possible. Restrictions on emigration limit personal freedom. They can prevent people who would be Happier if they emigrated to another country from doing so. Thus, emigration restrictions in this way increase suffering. Emigration restrictions also prevent intelligent people from getting a decent education, so emigration restrictions can reduce innovation and technological progress.
Emigration restrictions are a tool that is useful to authoritarian regimes. If authoritarian countries do not restrict travel, the masses will be denied knowledge about other countries and other political systems and ways of life. Many people would leave the country if there were not these restrictions in place.
However, in some situations, emigration restrictions can be justified. Restrictions on emigration prevent brain drain. Because of this, undeveloped nations can benefit by forcibly retaining their inventors, scientists, doctors, and others who are in need in these poverty-stricken countries. If poor countries allow their intelligent people to leave, these countries will likely not improve. Brain drain causes a massive development disparity, with the rich nations continually getting richer, and poor nations staying poor. These restrictions help to break this viscous cycle.