Moshe is sticking up for Ahron. But Ahron himself is totally quiet. [Ramban]. And when his two sons are Niftar, it says: ַויִּדֹם ַאהֲרֹן — Ahron was silent. It’s almost strange how Ahron is always quiet. Why doesn’t he react? Does he not have feelings?
We realize that Ahron symbolizes Korbanos, and Korban means being close to Hashem. Every Korban makes you closer and closer. When you see the insides of a dead animal, you realize the truth of every human being.
The beauty of your very existence sits in every Korban. The Chovos Halvavos in Shaar HaBechina is very involved in the concept that the basis of our Avodas Hashem is an expression of appreciation to Hashem; mainly for the fact that we are alive and healthy, and the miracles of our functioning bodies! A person who is heavily involved in these simple truths, has no time or patience for silly Machlokes, and even personal tragedies.