The upper classes in the UK regularly practice tone policing, where legitimate dissent is waved away as uncouth, even though what they say and do is far worse in private, and sometimes in public.
If you're looking for human dignity, I don't think this is its natural home.
This phrase is doing a lot of heavy lifting, because what one considers basic etiquette another considers a theatre. The end result is often that people gather in order to perform the spectacle of manners rather than use manners to facilitate a social gathering.