They probably could if that was the command. However Tony wanted to keep what had happened in the five years since the snap so he didn't lose his daughter, so the second snap couldn't be to put things back like it never happened.
I guess the answer to that is the stones can reverse what the stones did, so the people that haven’t died by the finger snap, can not be revived with the snap.
Rhaedas@fedia.io 16 hours ago
zod000@lemmy.dbzer0.com 10 hours ago
In the comics all the snapped people were contained within the soul stone. They never mention anything like that in the MCU, so it’s just that way “because”.