Well there simply no assurance there visa will be re-instated, and no matter if it is re-instated they can't leave the country or else they can't enter again, and considering the nature of it the ban would require Iran to grovel before trump to get it lifted in 90 days, it is most likely a permanent ban.
https://www.propublica.org/article/...ock-legal-residents-from-returning-to-america
That tells much about Iran when its reputation has such a negative effect on its population
Let me show you my gun collection.
Is your collection intended to protect your freedom or to mitigate restrictions