When did games start to be for adults?

ok so i have a quesition when did games become for adults i mean seriously i cant say a word in reach without some douchebag saying "GO SUCK YOUR MOM YA LEACH!!" or any other games.so since when did games become for adults also whats with all good games being 16+ can anyone just do freaking good game for kids too one that isnt made for four year olds?!?