Why shouldn't there be some civilian deaths in Gaza (not all 80k are civilians), is it somehow immune from the ravages of war? Gaza started a war against Israel, and Israel retaliated, setting itself a goal to completely eradicate Hamas and the like.
When you have terrorists embedded within the civilian population, and their goal is to maximise civilian casualties, that goal will be achieved.
Unlike Gazans, Israel isn't targeting civilians. It targets militants, but collateral damage happens. When the Gazan government continues to fire missiles from amongst civilians, and absolutely refuses to provide any kind of shelter for them (despite having miles and miles of tunnels), civilian casualties are inevitable.
Do you expect Israel to just accept tens of thousands of missiles fired at their own civilian population without retaliation and without attempting to neutralise the threat? Would that be expected of any country?
Gaza had 18 years to get their shit together and focus on peaceful building rather than hateful warmongerimg. They refused, and are now suffering the consequences.
As sad as it is for the innocents in Gaza, their blood is in their own government and militias.