I mean, the space marines are genetically engineered soldiers who are locked into their roles they inherited from the primearch who’s genetic ancestry they are from, all of which were crafted based on the genetically superior being of the emperor. The eldar and orcs are literally bio-engineered weapons weapons of a race that were basically gods. The Tau have a lot of layers racial hierarchy, bio-engineering, and similar levels of eugenics stuff going on. The tyranids basically just consumer biomass to filter for genes that can benefit their race and incorporate the new genetic data. I mean, unless you didn’t pay any attention to the game lore, I really don’t know how you missed all this. Like, this is the core of the game lore.

Beyond that GW have straight said that each faction is a caricature of some form of extreme ideology. The imperium are basically theocratic space nazis, the orcs are pretty much how the classical empires, or something like that imperium, see less developed human groups, the barbaric hordes. Etc.

Crone is more about personality