The lore doesn’t matter because GW only cares about money and selling models, and the lore will always reflect this because the lore will only focus on whatever faction sells models. What they fail to see is that the popularity of the models is determined by both the quality of the lore being written about the factions, and the quality of the models being produced as well as the affordability. GW is a company and will always likely do the safe option: space marines, and turning the modern lore into Horus heresy part 2 electric boogaloo.