I’m not saying it doesn’t happen, it is just not done for people like Pollard
Pollard is considerably higher profile, which makes it more difficult despite intense pressure from Israel for his release. There is a public square in Jerusalem named for Pollard, formerly Paris Square (Kikar Paris.) And the fact that Pollard was a US citizen complicates matters. Pollard renounced his US citizenship. Israel granted Pollard citizenship in 1995. So right now, we hold an Israeli citizen.