The Warrior of Light is not tempered by Hydaelyn.

[Rocl]

just about everyone in Eorzea believes in and has faith in the Mother Crystal, Hydaelin. This is likely enough to satisfy that criteria, so Hydaelin has no need of tempering or converting worshippers as she has plenty of them as is

Unless, they've gone back on this—this has been definitively shot down by the Lore team. One of my biggest gripes going from 1.0 -> 2.0 was how seemingly everyone suddenly accepted the idea that there was a giant crystal within the planet guiding us and granting us superpowers. Thankfully, someone out there somewhere heard my incessant mewling and brought it up in an interview:
https://gamerescape.com/2018/12/01/f...with-koji-fox/

GE: How did the belief in the Mothercrystal spread so quickly? Everyone’s all about the Twelve and then we disappear for five years and get back to everyone saying, “May you ever walk in the light of the Crystal!”

Koji: It’s all Scion propaganda. They’re passing out leaflets or something. (laughs) They want to push the whole Mothercrystal thing and get that out there.

When it comes down to it, there are tens of thousands of people in this world and most don’t know about Mothercrystals, just like most people don’t know that the planet is called Hydaelyn. There are no TVs, there are no science books, close to half of the people are illiterate. A lot of people are still living pre-technology…ish. I mean, there are water clocks and chronometers and people see how things are powered with aether. But, for the most part, people live in shacks or in these towns where they don’t know what’s going on.

The people you come into contact with seem to know this stuff. We’re not letting you talk to the rest of the people that have nothing to say. In a super open-world game we’d have people walking around town like, “I like farming because I need to support my family,” but we need to condense it down. Even the cities themselves are – in theory – way bigger, but we need to condense them down.

We give it a sense of being huge, but we can only add the people that are going to give you the information that you’re going to need for the game. We have to ignore the rest, but they’re there. So when the XIIth legion comes and (laughing) it’s like ten guys, is that a cohort? No, no, there are people there, but it’s condensed.

Essentially, the idea is we hear so much about Hydaelyn, the Mothercrystal because we associate with those who are in the know; the Circle of Knowing likely figured it out (or always knew! because they tell us to search for the One who granted us the Echo in 1.0) and told the Path of the Twelve. In the intervening years of the Seventh Umbral Era, the Scions of the Seventh Dawn formed and informed only the higher echelons of the city-states. The majority of Eorzea, and very likely the majority of Hydaelyn doesn't know of the Mothercrystal's existence.

Curiosity drove me to catalog the belief in the Mothercrystal/Hydaelyn further in the EN localization (because I really can't be bothered to do the other three honestly):

NPCs who specifically wish us/others "May you walk in the light of the Crystal" or some such (from greatest to least):
Minfilia
Kan-E-Senna
Naoki Yoshida
Urianger (his first utterance of this phrase is actually in the middle of when he's working with the Warriors of Darkness, lol)
Merlwyb
Y'shtola
All Three Grand Company Leaders At Once
Raubahn
Momodi
Miounne
Cid (to Noctis)

So basically, the only subscribers to this seems to be the Grand Company Leaders, the Scions, and the Scions' contacts in the city-states (the Adventurer's Guild innkeeps—I wouldn't be surprised if I missed Baderon because he used a few apostrophes.)

The usage of the term Mothercrystal follows the same pattern with one notable exception: A-Towa-Cant in the lv50 white mage quest. He's pretty much a literal ghost at that point though, so it feels pretty obvious he might know about the whole will of the star being manifest as a giant crystal in the middle of the planet.

And now usage of Hydaelyn! I didn't keep track of number of utterances here because there were a lot, but rather whether they meant the crystal/Mother or the planet. If they used it in both meanings, I kept them in the Mother/crystal/goddess barrel because they're obviously "in the know."

Planetary Hydaelyns:
Medrod (porter from Haukke unlock quest)
A broom (in reference to Gubal being the greatest repository of knowledge)
Cid (in reference to Midgardsormr/Shinryu conflation, and Alexander siphoning aether—could be argued either way, but seemed to be this one)
Jannequinard (various; including Hydaelyn isn't flat)
Mace (another astrologian, no mention of planetary goddess)
Levava (as above)
Erik (describing aether as vital to Hydaelyn, and Silvertear being the center of it)
Sylphie ("where on Hydaelyn can someone be")
Staelwyrn (about Serpent Reavers abducting people off the face of the planet)
Mikoto (I included her, because she doesn't seem to talk about the Mother Hydaelyn until after we get some information on the previous auracite bearers/Ramza/etc)

Mother Goddess Hydaelyns:
Naoki Yoshida
Ascians (Unnamed Haukke, Lahabrea, Altima)
Scions (Minfilia, Krile, Thancred, Y'shtola, Urianger)
Dragons (Tiamat, Midgardsormr, Hraesvelgr)
Grand Company Leaders (Kan E-Senna, Merlwyb, Raubahn)
Warriors of Light (Orran, Alma, Rama, Delita)
Hydaelyn
Honorary Mention: Louisoix

It's very possible I've missed some (I didn't find either of the twins!), my comb wasn't that fine-toothed (I didn't go through voiced cutscenes), but I think it's enough evidence to help support the claim in the interview and my point—the number of people who know "the Land is alive, so believe" is vastly outnumbered by those ignorant of it. Not everyone is aware that Hydaelyn is what she is, a giant crystal afloat in the aetherial sea—any revelation we get that points this way feels very... retconny (and that interview was recent!) Arguments for generic belief in a mother/gaia goddess and earth being the font of life etc I feel are separate.