Except the only one who could, his dad, understood this was the only way for Sasuke or the clan to live and surrendered himself to his son's sword. So basically Itachi is broken and everyone in the cast recognizes this. Which is why Sasuke was able to eventually forgive him. But there's a part of him that's still angry after all this time, because as evil as the Uchiha was it didn't justify killing all those kids.