A huge chunk of Space Marine 2’s story is about how Titus basically got screwed over by the Imperium for the sin of… treating Guard like human beings and fighting back against Chaos. A big arc is even that his squadmates (other Spesh Mahrines) don’t entirely trust him but learn to do so. And while I haven’t gotten around to it yet, I would be shocked if Owlcat didn’t take some pot shots at the zealots in Rogue Trader.