@EschatologistPretty much everything looks normal from the outside but from the inside it isn't.
The Dark Avatar is literally like a Dictator with his own set of rules. The following:
Yes, all nations have their leaders like Fire Lord etc but their power is limited as Dark Avatar decides the shots and approve the shots.
There are curfews and all that, akin to Martial Law. The society is pretty much living in fear and just have to accept the facts, this applies to those who knew that the Avatar is good and all. However, as years go by, some if not 70% are brain washed in a sense the upbringing is wrong making them believe the wrong stuff is actually right.
Which means there is resistance as well but they either survive or get killed. There is revolutionary/resistance army but smaller as day by day passes by.
Some of us are going to be on the Dark Avatar's side. Hope that answers all questions ;)
Room for one more?
Yep. Knock yourself out.
EDIT:
OOC is out!