Official people should show self-restraint because they are sources of authority. The impression I got from the article is that the author thinks Twitter users

Official people should show self-restraint because they are sources of authority. The impression I got from the article is that the author thinks Twitter users are sources of authority and that therefore some means of self-restraint or censorship is required. There's a difference between proclaiming you a source of authority (e.g. the WHO) and people labeling you a source of authority (e.g. Twitter users).