If the IDF are 'minimising' civilian casualties and have in place mitigations to achieve that aim, why would you flatten a whole building when the only threat coming out of it is single missiles from one small part of it. Not exactly a surgical strike is it?
When the Russians target civilians claiming they are aiming for military targets, the world is outraged - when the Israelis do it, some people applaud. Some sad individuals.
It will be "one tiny little missile trying to frighten somebody" next.
Hamas choose to put their civilians in harms way.
Hamas has one objective, destroy Israel. There is Collateral.
Any poor buggers in the building would be just fine if Hamas had not committed gross acts of terrorism. Cause, effect.
Join the dots.