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

[Eisi]

I wouldn't mind ignoring her from now until the end of time and just writing off Endwalker as bad writing, but the story keeps doubling down on her and dredging her up. We find out the Twelve are false gods put there by Venat and that we have to pray to them else the planet destabalises and untold calamities likely happen as the actions of keeping a planet unnaturally apart come to a head, or we end up using something like the locator crystal MacGuffin to heal Zero.

The whole Twelve revelation being one of the worst. Why is no one in the story horrified that should we ever decide to become an atheistic society and stop believing in gods that Venat installed herself, the world as we know it could crumble?

This is a general statement - to have the story self-consciously avoid mentioning or involving prior plot points would be horribly irritating. Regarding your particular example, the myths of the realm storyline was largely decided on prior to the release of Endwalker. To course correct as a result of player feedback would have been exactly what I wish Square Enix did less of. I want them to tell their own stories rather than appeal to me and my sensibilities. If their stories happen to suck, at least they are honest.

However I think part of the reason Endwalker ended up the way it did was because they went back on a lot of the things they originally set out to do and didn't stay true to their own initial vision, partially due to a belief that that's not what the playerbase would want. That's when writers check out - when they don't actually get to tell their story and have to maneuver multiple restrictive frameworks that don't allow for any genuine storytelling. It's just speculation on my part tho based on the story getting cut down to one expansion and Ishikawa's initial draft being rejected two days prior to the deadline.

Additionally, I think what you're saying is not true. I might have checked out too much to care, but I'm pretty sure nobody in the story mentioned anything about the world crumbling if we don't continue praying to the Twelve or any such nonsense. The star also isn't continuously artificially kept asunder, conversely it would require effort against the new natural equilibrium after the Sundering to rejoin the reflections.

I do not hold the view that the game offering different perspectives on Venat moving forward would serve to break anything.

To acknowledge Venat as a genocidal fool who should have told everyone and tried to stop the course of fate rather than stand by and do nothing as everything she knows will happen happened is to go against everything Endwalker believed itself to be. It has the story become meta in an unbelievably pathetic way that would willingly spit into prior writing's (that was done in two days mind you) face and throw a whole expansion under the bus for no reason other than as a weird excuse for failing as writers. I will never be in favor of such undignified weakness that has the writers prostrate themselves before the playerbase for having failed the way they did. I would take no pleasure in that, I would be embarrassed and hide my face in shame.

There is no way to fix Endwalker. Retroactively acknowledging that yes, it doesn't make any sense, will not serve to make the story any better at all and there is no way to transmute it into something beautiful nor is there meaningful storytelling potential in uncovering large swathes of Endwalker as basically a fever dream that didn't actually happen the way it did just because it sucked. The time for "different perspectives" on Venat has come and gone with Endwalker, an expansion that has doubled and tripled down on the one path we actually got to walk, a path that doesn't even understand itself. Besides Venat herself is clearly an unintended victim of a botched storyline that makes no sense in many many ways beyond just her behavior and character.