That is assuming Iran holds itself to the Geneva conventions, which ... seems like an extremely risky bet to make.
Prisoner exchanges are a pretty strong motivator for any group, even hardline ones. If the Taliban was up for exchanges I think the IRGC is pretty likely to want to keep prisoners for that too.
They're going back to the stone age, remember? The Geneva convention wasn't around then AFAICR.
What has Iran done to show it would not uphold Geneva conventions?
The US doesn't hold itself to the conventions, why should the country it started a war of aggression with?
Especially after the double-tap on civilians and first responders the US just did on that bridge. Or the threat for no quarters from the secretary of defense. Or the threats to destroy critical civilian infrastructure for water or power.
Maybe Iran is more civilized than the Barbarians attacking them.
We have to wait and see if Iran is fighting a woke war.
Hegseth explicitly ordered to give the enemy “no quarter”.
We are expecting Iran to honour an International Convention when US and Israel have squarely shat on every convention's face, so to speak.