Do kids get into cod nowadays?

I’m assuming 95% of this sub is 21+ at this point, which is weird bc we all started cod in our early teens maybe even earlier. Why don’t today’s kids play cod? Is it cuz Fortnite and other free to play stuff? Zooma said on stream yesterday 95% of his audience is 21+ on his twitch stats, A: that makes me feel like unc and B: why aren’t younger ppl getting into cod? It’s one of the most sold games every single year, is it cuz the league is 18+?