That's nice and all, but they used the excuse of "keeping secrets" in order to mind-control and torture one another, making one half of the clan's lives that of servitude.
All of Kaguya's descendants have Celestial Blood, but if anything, the blood of the Uchiha seems to create stronger shinobi than the Hyuga, so Momoshiki's sense of superiority is really unfounded.
Still gives no reason why the Hyuga started the hierarchy system and make the Branch family live in their servitude without any grain of knowledge behind the Main family other than the fact that they are
SOMEHOW superior. It just doesn't add up to what you're saying when the argument you're making is that the clan cast a slave system to benefit their own interest with their dojutsu and nothing more. I find your statement complete illogical.
If what you said are true then the Clan system would be pointless because that would mean that the the Main house have nothing special on their own . Seriously why on Earth does the Main House would go to such great lengths to cast a system to protect the Byakugan if both family does not differentiate from each other.
Given the context of the story, we don't know the secrets they are hiding and how the hell do they know so much about their celestial origin. And what is this talk of “Advanced Blood”?
Simply put You cannot disregard the narrative point and call off
"excuse" when the Hyuga Cast System is such a major plot point for the Hyuga Clan and Byakugan, it
MUST be brought up in relation to Bolt.
They never bother touching upon the Hyuga status even after Neji death which might entails that it still exist. Then it goes without my doubt that the Hyuga will play prominent roles in Part 3 and the fact that Momoshiki made a big factor about Boruto possessed the Hyuga bloodline as boruto was the only person (beside sasuke rinnegan ofc) capable of sensing him and trespasses time and space then this whole
"fate" that Momoshiki speak of might have some connection to the destiny of the hyuga.
The hyuga might have ties to the foundation of the Ootsutski clan because both branches of Hamura’s children posses the Byakugan, a clear trait among the Aliens as seen in Kaguya and Momoshiki. Even in The Last, we seem some hints of Hiashi being aware of the Ootsutsuki's existence.