And I'm saying that makes no sense to use as a basis for whether something is objectively (or as near to that as possible) lacking in some aspect or not. People do judge parts 1 and 2 of a trilogy, and not just after the trilogy is complete. All the more so if that trilogy is added to a franchise that has no habit of great twists or open-ended openings.
But there's a difference between a foreshadowed (albeit dimension-hopping) weapon crash landing somewhere and hiding a city in a hill some tenth its size. Consider it even just a matter of scale (just as one is left to wonder how all those warrior Xaela tribes can be so close to each other) or thematic lead-in (as ShB reiterates and compounds between ambiguity to conviction, but only vaguely touches over to what we see in NieR, simply because none of those connections were made obvious despite that it'd have cost nothing to make them so, only a bit more time and intelligent writing). They're simple areas which can be done well, or any degree of less well. There's no compromise to the Yoko Taro special style/ingredient/what-have-you.
Midargardsomr is not NieR, and is the only thing I mentioned as part of XIV's story, so... where is that strawman coming from?. "Even if I'd have preferred Yoko Taro work his magic on an actual XIV plotline" does not state that he already created any part of XIV story. The only connection I spitballed, no where near the post you replied to even, was the Light Waste, which likewise did not exist prior to ShB.
...Of all the examples, you choose that one? A dragon (established species) in the Azim Steppe (an established location) presented through a hunt board (an established means) to present a fight in a near-copy of the first boss area (an established fight) and includes aldegoat charges (an established mechanic), as an example of how a crossover does not benefit from connecting itself to the game through the whatever the game already have? They clearly thought differently, even if only to save costs at the time.