The Red Dawn looks more like it builds on the extremism of the OG Scarlet Crusade from vanilla. As a reminder, the reason they became hostile to everyone in vanilla was because they convinced themselves that anyone that was not a member of their in-group was “corrupted” and needed to be put to the sword. That’s why they weren’t friendly to the Alliance. Combine that fanaticism with the fact that the crusade has always been entirely comprised of humans and you get what we saw in that questline.