Back when she discovered Hagoromo's betrayal, she fought Hagoromo and Hamura, and the battle between both sides lasted for more than a month.
What she controlled was the Ten-Tails.
In other words, the Divine Tree.
Meanwhile, Hagoromo and Hamura controlled Susanoo like Madara Uchiha's.
But Madara's Susanoo-clad Buddha together with Hashirama Senju was no weaker than the combined strength of Hagoromo and Hamura in the past... No, it might even have been stronger.
But.
They were clearly both powers inherited from Hagoromo, so logically, they should not have been able to surpass Hagoromo and Hamura.
So... was the reason for this growth... that Hagoromo distributed Chakra to others, and after the tempering of time, the ninjas eventually learned to use Chakra, developed it further, and ultimately achieved power where one plus one was greater than ten?
Then...
Perhaps she had found the answer to what that foolish child Black Zetsu had said.
Yes.
Kitahara Kaede was the fourth child she had created. Unlike his two unfilial older brothers, and unlike powerless Black Zetsu.
He possessed the power developed by the entire ninja world.
And that power, only one-fourth of hers, had long since surpassed her own one.
"..."
Kaguya Otsutsuki.
Ancestor of the Ninja World—Kaguya: I never thought this day would truly come.
And she also understood why Kitahara Kaede had not released her.
Just as Shukaku had started running earlier and was immediately discovered by Momoshiki and Kinshiki.
If she appeared...
She was naturally a massive accumulation of Chakra.
She would definitely attract the attention of the Otsutsuki Clan, and then... it might not be just one Momoshiki or Kinshiki attacking her, but other members of the Otsutsuki Clan who had consumed one, two, or even ten Divine Tree Fruits.
So.
Kitahara Kaede's refusal to undo her seal... was