To be precise, this thread is about Indira Gandhi-led Government of India's decision to release 93,000 POWs in exchange for next to nothing following such a successful campaign in 1971. The exchange actually happened in 1972.
India could have stuck to their guns and said that while most POWs would be repatriated, the ones accused of severe war crimes would face trials. Plus, the POWs could have been released in batches and also linked with Pakistan taking along those Biharis and others who supported Pakistan till the end in 1971. Bhutto understood well that had Mujeeb been hanged, the repercussions would have been far more severe for Pakistan, internally and internationally.
India held all the cards and we frittered them away, just because someone wished to appear as a stateswoman and was reliant on some very dubious and very poor advisers.
Within 2 years of this release, we entered into a disastrous tripartite agreement to provide amnesty to all war criminals and soon after Mujib was assassinated and the Islamist Zia Ur Rehman ceased power. Effectively, East Pakistan was back again and this time led by a Bengali, which mean we could not intervene again, even if we wanted to.