Aside from the fact that it was a perfectly reasonable remark under the circumstances, I see no practical difference between Reploid Productions' Facebook post and if she had, say, made the same comment in real life, over dinner with some friends; it was a private remark not intended for public disclosure and we shouldn't censor players for things they do or say off-site. If Dread Lady Nathanica had come online saying "This is what Reppy said to me while I was round at her house for cheese and wine tasting* yesterday evening..." then I don't think any of us would have considered the remarks at all relevant to anything.
This discussion's not about what Reppy said though; this is about what Nathi did:
Nathi linked to the personal Facebook page of a NationStates player, potentially providing information that could be used by other players to cause that person actual real-life harm and grief. The fact that Nathi believed (innocently but mistakenly) that the profile was already public knowledge and had adequate information protection is probably the reason she only received a warning; if it had been done knowledgeably or maliciously, this could reasonably have been a DEAT offence - especially since her objective in linking the Facebook post had been to undermine Reppy anyway. Ultimately, given Nathi's background she ought to have known better than this even if the rules around Doxxing weren't altogether clear and the punishment in this case seems absolutely appropriate.
*While listening to Bach and wearing formal attire. In my mind, the mods' personal lives are all suave and classy and apparently set in Downton Abbey.