>>43308307He didn't really even display any hubris though; at least not in the novels. I mean after he was resurrected, sure, he displayed hubris and every other shitty quality a person can display. But before that he was charisma, wisdom and humility incarnate.
Which is why people followed him; because he could do no wrong in the eyes of his subordinates. If he was just some chest-thumping asshole in terminator armor, the second he came back to life and started ordering the wholesale massacre of civilians and shit, every single Astartes would have been like "Um, no, fuck you; I've been taught by the wisest and most learned scholars of the galaxy to the pinnacle of human courage and wisdom, I am not going to betray my oaths because some big scary fuckhead tells me too."
They followed him because they loved him, and in their eyes, nothing he could do was wrong. And even then, a great many of them refused (and were massacred on Istavan).
He's supposed to be styled as an anti-christ type figure.