Keep in mind that a big contributing factor to this discussion is simply that Hydaelyn was not planned to be a part of 1.0 (as far as we know), and the Twelve were going to play a much larger role according to early interviews with then-loremaster Kenichi Iwao. In those days Hydaelyn was simply an unseen songstress; not even Minfilia knew her. Shalayan apparently kept it on the hush that they attempted to make (and perhaps made) contact with her in the 1300s, a fact not revealed to us until much later.

Quote Originally Posted by kaynide View Post
What is she to the average joe on the street?
In most places, not much. Minfilia had good PR with the Grand Company leaders. Most people of contemporary times that we never meet can barely conceive of what a planet is, never mind that we live on one, never ever mind what it means for it to have a will. They're mostly Twelve-oriented.

Quote Originally Posted by kaynide View Post
If a person were to say “Hydaelyn speaks to me!” would the reaction be one of “this guy is crazy! He thinks the trees are talking to him!” or “you must be one of her chosen!”
Overwhelmingly the former. This is why Minfilia disguised her original group as one of myriad cults in Ul'dah.