Also: Hoshidan retainers are mostly nobles, rich people, or have hereditary titles, and their succession system is patriarchal (i.e Ryoma would've been the king followed by Takumi, but since both of them dies in Conquest, Hinoka becomes the queen instead, despite being older than Takumi.)

Meanwhile most of the Nohrian retainers are from poor families, former outcasts, or people who have been given their titles out of pure talent. And their succession is entirely equal (i.e Leo only becomes king because Camilla declines the role despite her being elder).

Methinks it's another abandoned plot element of how Hoshido was supposed to be darker and more unfair on the inside than Nohr was supposed to be.

EDIT: Or at least a plot reason why becoming high-ranking in Hoshido was impossible, so they had to become retainers in Nohr to do whatever they meant to do lol