Free speech isn't just an American's right, it's a human right. Protecting it is necessary for prosperity and freedom whether you're in the US or in North Korea. I never said "Reddit shouldn't do this because it's against the constitution."
Reddit shouldn't be doing this because it tends to violate an innate human right and because it will destroy Reddit. And since I see you're inclined to take my words out of context I have to say the following: Your next argument would probably be, "yeah right. Posting revenge nudes is a human right" and my reply is this: As I said in my first post, which particular speech is being threatened is irrelevant.
Censorship is a ball and chain for the soul of man. Whatever the speech in question, the act of censoring it turns the latch that locks the shackle. Whatever the first link, others are added until a great weight is there. And placing that weight on a single family, a forum of millions, or a large and prosperous nation are all immoral.