There is a power imbalance, I don't think anyone is saying Seekers are egalitarian in that regard, but 'patriarchal' has a pretty set meaning. Breeding males have main rights to the kids, and that is power, but they don't have power over all, just their own kids. A Nunh has no real authority beyond what is given to him, there's no tribal law that says he has any power over his kids or women he mates with, if a Nunh does something out of line nothing stops a female Seeker from going 'uh no, that's not cool', the children are raised (seemingly) by the tribe as a whole not just by their father. Obviously a Nunh has influence, and is respected, but control isn't inherent in the position.
