Wow, that is depressing. I would definitely be ashamed to implement a feature like that.
I could easily imagine (especially at a place like Apple where there's a ton of internal secrecy), the ticket for implementing removeEmoji() could have been pitched in a much broader fashion: perhaps there would be a "child mode" that would remove the middle finger emoji and others like that.
Notably, the code specifically looks for the "CN" locale, and calls "removeEmoji".