If there's anything this game isn't, it's realist. It treats war and conflict as a complete pastiche of children playing soldiers and indians. The opponent is evil in the sense an orc might be, and the good guys are as well, even if they're obvious racists or otherwise ass-clowns. Winnie The Pooh-land is the victim and their murders are brushed aside with the warm laughter of teenagers. Women give unproblematic births in moving tanks which are getting fired upon. The protagonist's first kill is barely noted. Meanwhile, every downed ally on your own side is occasion for strong remorse. The few Empire soldiers who get to say a few lines are cartoonishly villanious. Every character wears make-up and hair-styling into battle.
Basically this game is children playing at war with the dream toys of two ten-year olds.
So in fact the opposite is true: a 12-year-old soldier makes sense in VC precisely because the game is completely removed from any realism at all, sans a pretty down to earth aesthetic, the genre considered.