If you step back and try to take emotion out of your consideration, Israel’s actions don’t support that statement. Israel has enough military power to have completely erased Gaza months ago, without sending in a single ground troop, and there would have been absolutely nothing Hamas could do about it.
The situation as it stands right now is basically a textbook example of why the concept of war crimes exists. Taking hostages is a war crime, as is having your fighters not wear a distinct uniform. That second one is critical here, because when that law is broken, it turns civilians into targets.