I highly disagree.
It’s a shame that they did not explore it, but the most interesting thing to me from the artbook is the Diamond lore.
Gods, firstborn mortals, divine half-children, all always know exactly what to do in myths and story. Gods know and have mastered their powers and set about creating the world we have in all their wisdom aside from their intriguing adventures. Firstborns are guided by their creators, and fade away for the younger generations. Demigods have teachers and patrons to point them to their destiny.
The Diamonds subvert that. They had supreme power, and absolutely no idea what they could do with it or why they existed. They just started making shit up. White had the ability to control others, and assumed since her color was white and thus reflected all other colors that she must be the only true person and all things just fragments of her as a kind of Godhead, like Eru from Tolkien or some Abrahamic and eastern Dharma-based faiths. Except she was totally wrong.
They just assumed that they were the only intelligent life and destined to exist everywhere and unite the universe as one single unchanging thing, which was also wrong.
The fact that once they learned that their initial beliefs were incorrect and they just set off in another direction without a fight is just as interesting. No need for the death of an old pantheon to be replaced by the next, no destruction of the universe to begin another cycle. Just starting over with a new idea because the old one didn’t work, and as the immortal undying eternal firstborns and parents to all, they don’t need the angst from their investment being for nothing.
Most of all, as divine beings they want worship. But they’ve happily swapped obedience for love and reverence, swapping the titles of divine queen for divine mother. What they would have wanted for themselves.
This playful deconstruction of myth and religion is VERY interesting to me.