I was wondering what the Admins and Mods had planned for them, if they are going to be removed or anything as they were part of the old AG rank system and no new players can achieve them?
Well you can't achieve the rank ones like the duke ones, and There were no other quests, so yes they are gone, except for the people who already earned them.
The ranks have been removed already, however the "legacy" quests, as they are sometimes called, are there to honour those who spent their time earning the old ranks. I believe, the legacy quests are meant to stay, no new users can earn them, but that's sort of the point. The quests honour the legacy of long time users.
I can understand how it is a bit frustrating to a someone (especially a somewhat perfectionist like me) who may want all the quest, but can never get those legacy quests. There are about 3 or 4 legacy quests I will never be able to get, but eventually I got used to the idea of never being able to have all of them :]