Tranquility hid your post because you made an announcement about other people's account status. Her response was clear and to the point. Account status is private between Jagex and the account holder. Since it is private, it isn't appropriate for the forums.
The thread you mention is open in case the OP would like to reply and there is no rule breaking on the first post.
Finally, please do not twist the spirit of Tranq's statement. While we are indeed helpful, this is not the place to post when you disagree with our actions - which is essentially what you are doing. That's what the
Forum Moderation Review
thread is for.
The image has been removed so I can't determine the context. I don't know if the context was negative, but the current context is neutral/positive with no details. Given that, I have not hidden the post.