If your answer is “Hamas is there,” well they were somehow able to raid a hospital without killing everyone inside it and still get a whole bunch of Hamas people, so maybe they should do that instead of dropping bombs on children.
As you acknowledge, they are targeting Hamas, who often attacks them while hiding in areas full of children. Going in without air support into a well prepared guerilla fighter's den is likely to cause a lot of casualties. Even though that is acceptable every now and then like in the hospital that does not imply that's a viable strategy for all of Gaza.
Hamas counts on this "think of the children!" and the bad PR it causes, that's why they do this. They also want Israel's hands to be bound so they can do Oct 7 over and over again.
The right move is to minimize civilian casualties but not stop until the job is done, and that's exactly what I believe Israel is doing.