It's been easy for the Israeli government to attach a total Hamas surrender as a condition for stopping, as they know it'll never happen.
In the unlikely event Hamas was to announce their total surrender to the IDF, the Israeli government would be put in an awkward situation that they never expected to happen, finding themselves with a military occupation of a traumatised, ravaged, deeply resentful population, the world's governments clamouring for them to do something that they have no plan for. It wouldn't end well for anyone.