It is well established that Hamas is using civilian areas and infrastructure

Established by whom?

Can you tell me why Hamas gets carte blanche but others such as Ukraine are criticized in similar circumstances?

On what planet has Hamas received carte blanche? Gaza is currently being carpet bombed. This is exactly what Russia did to Kyiv in the opening days of the war, and it seems clear that Israel and Russia are running identical playbooks. Mass murder of the population as a form of ethnic cleansing is now the standard military doctrine of encroaching powers.