
Originally Posted by
zbtiqua
snip.
I'm going to do a TL,DR version just for you so that you understand why at least a great part of this quest chain is necessary by design.
=> first off, Ishgard has refused strangers in its walls for many centuries before the events take place. The events from 2.4 and onwards are the sole reason why they made an exception for you.
=> 2.1 and 2.2 bring some political baseline for future development in the story. If anything, those patches could get a shortened questline but not by a lot. The domans and Yugiri are introduced.
Also, Elidibus. Super important guy for Heavensward, as he is likely to become either a super villain or a controversive ally.
=> 2.3 brings ALL of the basis for the development of the story onward. Uldahn political mess, the fundation of Alphinaud's Grand Company... the grand finale bringing you in Ishgard starts now.
You also make contact again with Haurchefant de Fortemps. He is the guy bringing you to Ishgard.
=> 2.4 patch brings Aymeric, Ishgardian general. You help Ishgard by taking care of their problems with heretics. That makes you appear as an ally rather than a stranger.
=> 2.5 : Ul'dah is more and more in troubles, but the Crystal Braves are too. Nasty stuff kicks in, you lose the benediction of Hydaelyn, the Scions are attacked (and one is killed), we kill a dragon to save Ishgard's ass and we finally reach the climax where the sultana intends to abdict during a feast made to celebrate our victory.
Boom, the Sultan drops, and you're framed, accused for her death. All of the scions go missing at best, or worse, so that YOU can flee. You end up alone, without anywhere to go as the Crystal Braves betrayed you and try to kill you.
That's when Haurchefant and Aymeric (respectively son of one of Ishgard's leader and general of the fighting troops of the city) manage to get you a special "3 people only" (you, Alphinaud and Tataru) authorisation thanks to your help against the heretics and the dragons.
For this sole reason, you are now the first and only strangers allowed to come in Ishgard in centuries, and thus you can enter the extension.
Please bear in mind that I am by no mean a writer and did this without putting much in narration. This is just a poor quality, fast written short version of a well made quest chain bringing in many elements together to reach a conclusion which was really awesome.
There is simply no way you could have ever entered ishgard without going through those quests.