I'm with you on this, I feel bad for what I suspect is a majority of Gazans who fear Hamas too much to speak up against them. That's the biggest issue with OP's argument.
But Israel isn't targeting them. Israel is doing everything it can to warn them of the exact buildings it's targeting, and Hamas is doing everything it can to keep them in the warzones and in the buildings, because it wants them to die, it wants them to be "martyrs" Its leaders have made this clear in many interviews. They talk about how they have six kids in the hopes that three of them die.
War is hell. Nobody is taking this lightly. There will be civilian casualties. That's a terrible thing. Allowing Hamas to continue its control and its rampage is worse.
Allowing them to continue to oppress Palestinians, target Israeli civilians, fire rockets (more rockets have landed in Gaza than in Israel!)... They dig up water pipes to turn into rockets. They steal fuel from power plants that could be used to power hospitals and desalination plants. They set up their bases and fire rockets from schools, hospitals, mosques, and residences. They are demanding war. Their founding charter entirely rejects any kind of peace at all. It's not an accident.