[Theory] Kaguya Otsutsuki can and might still be revived later on and here's how!

[Draxus]

Why throw in addition questions to the story this late in the series and not answer them at all? That's just terrible story telling. It's likely that is going to be the plot in the New Era Project.

I'm not saying it's good story telling, just stating the fact that just because questions are raised doesn't guarantee you'll get a clear answer. Just because the expectation is reasonable, doesn't mean it's not also naive.

They are the roots of the God Tree as stated by Hagoromo and I doubt they are being kept alive through chakra since the point is for it to be one.

How else would they live? Chakra is life force, the tree consumes and distributes chakra. It seems to be the most logical conclusion. Either way that doesn't change the fact that the chakra was completely drained from them, or they would be dead.

Judging by Shikamaru's encounter with the God Tree they shouldn't even be able to move.

What's that have to do with anything? My point is if they are alive after IT is released, they'll get their chakra back naturally. You realized Shikumaru was pretty much dead, right? Are you saying a ninja with almost all chakra drained would never be able to recover on his own, given time? Chakra recovers overtime on its own, eating, sleeping, and medical ninjutsu all increase this rate.