You can see the far-reaching impact of the odd "Violence yes! Sex no!" American morality in so many places. One recent example that struck me: GTA Online, a game rife with violence and destruction and even sex (surprisingly for an American game), but the chat has a profanity filter that filters words that are otherwise present in the game's scripted dialog and soundtrack left and right.
It's made by Rockstar North in Edinburgh. Almost all GTA games have been satires of American culture made by a British company.
1978: https://www.youtube.com/watch?v=qNLOXJw0aUU
"better get down off that horse, sherrif: we're fixin' ter fuck yeh, now ... but we're not gonna fuck yeh fast; we're gonna fuck yeh sloooooow"
European self-righteousness is getting annoying on this forum.
Or it could be even simpler and more practical than that, most children don’t have weapons, but they do have human bodies.
Perhaps Apple thinks that the risk of seeming prude is worth it to prevent some kid from falling into sexual abuse and the bigger risk of mom and dad not letting them shop freely for apps.