I just don't agree that Orion was really getting arrogant. The only time where he was even remotely arrogant was in the alley with the junkies and even then his reaction was perfectly warranted, if some bum comes demanding change from you punching them in the face is the correct choice. If anything his only screw up was by not taking it farther and making sure the enemy was down for the count. The only reason the situation went pear shaped is because a junkie who likely didn't have 2 eternals to rub together SOMEHOW had a gun. If they were proper gang members then sure I can see that, but junkies? At most they would have a knife or a broken bottle. Also if you're going to mug someone and you have a gun you pull that out first, much more likely to get the money without having to fire a shot.
I mean the entire chapter Orion was constantly questioning himself and his enemies. With the werewolves he was confident but also respected the enemy enough to be wary of him and while I haven't seen the vampire route I'm sure it's pretty similar. He even questions if what he is doing with the girls is right and after thinking about it comes to a logical conclusion, it's probably not the right one but the fact that he even stops to question it shows that he is aware of his actions and not just assuming he is the god king and that everything will work out.
All in all I don't think Orion earned that shit from Idriel. If you wanted him to earn it then the werewolf/vampire parts would have had him just assuming he would win without challenge. You would have removed the part about him being excited that Coyote was an actual challenge and replaced it with something more like "Coyote is better than I thought but still a chump not worth mentioning" you would have him NOT questioning his relationships with the girls and just assuming he is so badass it's obvious they would fall for him. Having a single encounter where he shows a level of earned arrogance that goes sideways in a kind of stupid way does not warrant the "You deserve this because you were being arrogant" speech. At best it deserves a "This is not how things were supposed to happen, someone interfered with your destiny" or "You were unlucky"
If you really wanted to hit us with the consequences for arrogance trope then there should have been small moments where he truly was getting arrogant, then have Idriel chide him in one of her talks, something like "You are doing well but be wary of arrogance and do not let it cloud your judgement" then hit us with what we got and it would feel earned and right. This feels like Cari wanted to have a morality moment and threw it in because it would make a good cliffhanger not that it made sense to the story and character.
Aside from all that it was a great chapter, a little bit short but with all of the theory fodder it totally makes up for it. Now I just have to work out if Orion is going to survive the incident, become like Thanatos, or have the world kind of reset.