What's the point with that quite lackluster story in Endwalker?

[Midareyukki]

They kind of dug themselves into a hole by making the EW role quests totally optional as it necessitated that whatever threat was involved in them had to be minor enough as to be entirely skippable which further downplayed the threat of the Final Days.

What I find particularly annoying about this is how they are adding more to the EW role quests. Stuff that has the absolute most faintest guiding thread. It ends with Nerva, solving not only a lingering question from the MSQ but also from the sidequests. And now they're adding information on the Four Fiends. I fail to see what "beating up a bunch of Blasphemies" has anything to do with "a Hecteye wants to experience our world in exchange for information on Splinter and his four pet turtles".

Also, let's compare why Endwalker fails where Shadowbringers succeeded. Because technically both cases had us deal with "minor" threats that were personal to NPCs we knew, and in doing so, unveil more about the world and their stories. Because it's really curious.
Shadowbringers nails it by making the four warriors of light interesting characters. Throughout it all you're being told their past lives and how it influenced their story.
Endwalker fails by casting out any investment and beat around the bush. Not always, which reveals some inconsistency. The characters that they expand upon either already had their moment and were really just repeating the same key, or were so far past us that it really feels like an absolute chore having to go through that sob story all over again. But while some stories were a logical continuation of events that had happened very recently (Limsa showing us that not everyone is so keen to forgive and forget as presented in the previous expansion), others were just ruminating on buried content.

You only had a basic gist of who the Warriors of Light were as a group, you didn't know them directly. We got a three-way win: you get to experience the tale with Ardbert and give him closure, you find out more about the Warriors of Light and you even get to know more about what's otherwise just a large island surrounded by a desert planet. All while shedding some light on the calamity itself, slowly uncovering a mystery.
Endwalker offers you further closure on characters that either already had it or didn't need it. Harping on themes and characters that already had their piece isn't going to work. And while sure, you can always add a bit more for the sake of continuity, at some point you must wonder whether you're really "giving continuity" or whether you're beating a dead horse. Fordola didn't need another moment to establish that "she's fine but must repent". That was clear after Lakshmi. Or the Heavens' Ward quests. We didn't need to go through this drama again. Not after the DRK quests, not after Ishgard Restoration and the delivery NPCs, and bleeding hells, not after the MSQ itself already made their losses clear.

Then there's the mystery and its implications. Throughout SHB's quests, we wonder "Who's she? She wasn't around before...". And no quest tells you anything major about her. Only at the end are we given the truth about her. It leads to interesting interactions with our further adventures. We go to the moon, we beat up Mommy and Daddy, we open portals to the Void, they comment on all that. And it provides continuity to Unukalhai's until-then disjointed story and hypes future adventures.
Endwalker falls flat on its face for this one. Nothing is set up for Nerva than the MSQ and sidequests in Garlemald. We do the dance with Nerva, we talk to Garleans and convince more to join up and try to work together with the rest of the world... and then...
Out of nowhere, after Zero takes a nappie, we're treated with a Hecteyes who exposits on the bosses we just beat up. Why? And what does this have to do with Nerva or Blasphemies? It just makes me feel like to obtain this information, I had to go through a chore. And Nerva's death really only resolved one area's story, there's nothing more to him, it doesn't connect to Golbez.

Finally, there's the issue of tone. Shadowbringers sets its job quests during the Flood of Light. Even after you're done with Hades, there are still Sin Eaters around, so the existence of the other Virtues doesn't clash with the ending. And even if we go through Eden, there's only the hope that the future will be better. The Sin Eaters are still a present-day threat. Prior to Amaurot, those quests have as much tension as the rest of the expansion. Past Amaurot, the tension is lowered, sure, but the danger is still real. We know what they're capable of, and Shadowbringers always had that "doom is upon us" feel to it.
A feel that Endwalker failed to live up to despite it being released under an "End of Days" banner. The tone was "doom may be upon us". With how weak the execution of the Final Days was, the presence of Blasphemies worldwide is indeed a tension-building prospect... that leads nowhere. The threats are too localized, the deaths are minimal and the effects are cosmetic at worst. "Local impact" isn't what you're going during "the end of the freaking world". Sure, there was the potential for things to go sideways should we fail. But this is Final Fantasy. That we "won't fail" is a foregone conclusion. The writers forgot how to be genre-savvy. Which is funny because Shadowbringers was. Obviously we were going to be fine, but not only were the consequences going to be long-lasting if we didn't succeed at the right time, at no point other were we given any moment to feel comfortable about our situation. On Endwalker, I felt I've fought worse... And having your major antagonist show up at the end and literally tell everyone "Really? Haven't you fought worse?" makes the writer look insecure.

[Tsiron]

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Really well put, nice job!