So did they entitled a new Azure Dragoon?

[Cleretic]

Azure Dragoon isn't actually 'the one strongest Dragoon' or 'the leader of the Dragoons', it's just a title for a Dragoon with a particular role in protecting the Eye of Nidhogg that they get power from; it's certainly a very important role only given to trusted people, but they aren't King Dragoon. If you're playing through Dragoon's jbo questline, then you're an Azure Dragoon by the time Heavensward rolls around. There's likely been more than one Azure Dragoon at once multiple times in the game world's history. Aymeric's never been one, but is seen as having a figuratively similar role for at least a while.

I'm not 100% on where in the story you are, but as of about the end of patch 3.3, the situation is:

There's no Azure Dragoons anymore, not because they haven't appointed one, but because the job no longer needs to exist as it has for the past thousand years; with no Eye of Nidhogg to guard, what's the point of appointing someone to the job whose entire description is 'protect the Eye of Nidhogg'?