New Era Darui scales nowhere except to that Gokage and Sasuke vs Momoshiki and Kinshiki fight.
Kaguya's grandson's reincarnate isn't a mere fragment of her power.
Naruto isn't weaker than pre-Juubi Jinchuriki Hagoromo.
Kaguya was planning on turning all of humanity into Zetsu, which means millions upon millions of Zetsu. Not sure how people think millions of Zetsu is a fodder resource, especially since Kaguya could use them to amplify herself by absorbing their chakra on a global scale, like she did with the Infinite Tsukuyomi victims against Team 7, and then massively amplifying her power.
The narrative intention is pretty clear that Momoshiki and Kinshiki, at least as a pair, were supposed to be threats to Kaguya and she was scared of them although they're kind of underwhelming compared to her, not gonna lie, but that's just Boruto in general compared to Shippuden God Tiers.
Naruto and Sasuke are supposed to be stronger in the New Era than EoS but they haven't even managed to equal initial Biju Mode Naruto in destroying mountains yet, yet alone the feats on a global scale around EoS. Hell, even Pain has better DC feats.