I'm going to be very childish to a stranger who scolded me about running a red light.
Why do you think that being childish is a proper response to a scolding?
I don't like people who treat me like a child.
When someone criticizes you for doing something dangerous like running a red light they are trying to help you. The way you plan on acting towards them to make them feel bad isn't the way to handle things. Take in the input and change your behavior
But people are annoying when they treat me like a child.
What I'm trying to tell you is he isn't being childish at all.  He's looking out for your best interest, as well as the safety of other drivers.  Take his advice to heart.