Satoshi was the creator/admin of the forum. Back in the day, people can post in the forum as "anonymous". No sign up was required if I'm correct. Satoshi added the post as administrator. I don't think there's anything special. Moderator may check what has been edited as they most likely has the right to check the original version of the post.
Reasonable enough, because after reading the op, I was beginning to wonder if moderators have the power to edit a user's post or comment even till this day, that would have been really really nice 😁 ~
sarcasm