Comment by stratocumulus0

One major difference is that it was extremely difficult to leave Eastern Europe. Borders with the West were fortified and even in the unlikely event of getting a visa issued, the government would make sure that your loved ones were left behind, forcing you to eventually come back.

The citizens of Iran, in turn, are free to leave the country as they wish. In fact, the official policy is that if you don't like it here, then you are are supposed to move out.