What new rule are you imagining? Telling various feuding posters to stop pursuing a specific line of abuse for the duration of a specific thread has been a standard practice for years.
It isn’t prohibited in Great Debates. It was prohibited as a direct epithet for a specific thread. With a negated major, your conclusion fails to follow.
On the other hand, referring to other posters with epithets such as “Repugnicans” or “Dumbocrats” is prohibited in Great Debates.