Endwalker story doubt: spoiler alert

[Kozh]

And that means that this is ultimately an argument about minutia for shallow point-scoring, because arguing that the escape plan couldn't have worked according to evidence that she did not have completely misses the actual story around the escape plan in the first place, and basically only serves to create artificial points against her. And personally, I'm not interested.

I'm freaking sorry?? But you're the one who brings up Venat in the first place. Even OP in their post only ask the "how can people on moon survive if...".

And then on my first reply, I 100% focus on your questionable takes on meteion's nature, as shown here:

Okay, three things here:

A: You're assuming Meteion even knows about the moon enough to keep track of it. It wasn't there when she left as far as we know, and her despair waves weren't getting anywhere near it.

B: You're also assuming Meteion cares enough to look, or even know if people would've left, and I genuinely don't think she does; I don't even get the idea she's keeping tabs on Etheirys now. Not only that, but recalibrating her aim to follow the moon actually goes against what her goal is anyway: to test Etheirys itself against the inevitability of death.

Meteion's what I call a 'broken robot' character, even if she isn't that in a literal sense; she's got an outlook and plan that's rigid, completely logical and internally consistent, that happens to be utterly broken when looking at it externally. Therefore, if her goal was simply to aim and fire at Etheirys to prove it can't stand her oblivion, it doesn't really matter to her if people escape, nor to keep track of the people that do; the notion of escapees just aren't part of her logical series of parameters, nor are they relevant enough to her goal to factor in anyway.

And C: Of course, we should also remember that Hydaelyn's Moon Escape Plan was ultimately a very visible and obvious (to the people on the Source; again, Meteion didn't see it) Plan B or C masquerading as the Plan A. Her goal was always to get us to follow Meteion and try to stop her, the moon was just a fallback that also existed to provide plenty of hope for the future and competent space-travelers. So the escape plan having some holes makes sense; if it was surefire and foolproof, it wouldn't be the backup plan.

She did focus her beam towards etheirys, but that’s to break the barrier. And you know she notice the instant it broke/zodiark died. Her song of oblivion, which to hasten heat death of the universe, as the name implies, affect the whole universe. There’s no escaping that. Now you might say “well that’s different than FD”, yes but it shows that her attacks could (and did) affect everywhere. The moon plan will only buy them little time, since it no longer have zodiark in it.

Second, idk where tou get the idea of her focusing to destroy the planet only. Ever since ktisis, up to UT, she repeatedly said that her action is a gift for mankind. Her focus is “saving mankind from suffering” by ending them.

Only for you to once again goes on a tangent about how Venat doesn't know the future etc., when nobody talks about her.
Like you said, it doesn't matter to the discussion because that's not what OP asked.

Ignore all of my points about Meteion, because they don't truly matter.

So we should ignore your points about Meteion, but also you're not interested in talking about Venat's decision... /hmmmmm

The moon escape plan is the same way, although thankfully with less moral concerns

You want to play this game? Sure.

Let's ignore that the plan resulted in: A) the star died and those souls in lifestream gets eaten by meteion, and B) the remaining shards are left behind.