The doctrine that all non-JWs ( and even some JWs who aren't pulling their weight - the so-called "Kevinly class" ) will be killed at Armageddon was very much promoted when I was young ( in the 60's / 70's ) with many graphic illustrations of babies and children being killed ( such as in the old "Paradise book"). . But in more recent times , the Society has ( understandably ) been much less vocal about it. They tend to focus on the concept of "the wicked being destroyed" , whatever that actually means in practice.
The Societies reticence to openly discuss it enables many JWs to either deny it or mentally make some kind of formulation ( eg "Jehovah can see into their hearts" etc ) to try to reconcile the cognitive dissonance.