The IDF needs to try to isolate groups holding hostages so the groups can easily be identified if something worse happens to the hostages, such as getting murdered. Groups might simply tie up the hostages and move away from them since simply being identified by the IDF as a fighter will mean less confinement time than being caught as a hostage holder, brutalizer or killer.
Asking Palestinians who don’t wish to fight or get killed to move into safe areas will facilitate the IDF’s job.
There are probably very few hostages that can be released. Many are probably dead already and more than a few of those still alive will be killed by their captors to cover up for the crimes committed by those holding them.