Hamas cannot return the hostages. They know hostages are the only thing preventing their extinction.
In my view, after 2,000 were killed on Oct 7, the 150 hostages should be considered by one and all as dead already. Only the weak allow hostage taking to be rewarded. And make no mistake, rewarding hostage taking is exactly what has happened!
For every hostage returned, something like 8 terrorists were released from prison in exchange. They in turn, can kill more Israeli's and take more hostages, repeating the cycle of weakness succumbing to evil.