The Kyrian take vows to remain impartial, and to ferry the souls of those they collect to the Arbiter, and later to wherever they are judged to belong. Devos and Uther broke those vows and judged Arthas by themselves in secret, bypassing the system.
Arthas was likely Maw bound anyway, but the way they did it leads to dark places.
It just wasn’t all that clear from the clip itself … or why it was “such a bad thing”.
I guess it just spawned some threads that didn’t make too much sense. “Your soul is damaged”, but we will make you Kyrian anyways. We will wait until Arthas dies (like he would eventually) and toss him in the Maw like we would get tasked to do eventually as well.
So yeah I guess the ‘no-no’ was that they skipped the judgement step. Was that clear in the video that such a step exists? All they said was that “uther was chosen” not who did the choosing - could have been the lady in the video.
Also also - at the meeting they claim the whole situation is “impossible” as if they can’t just bring Uther to the meeting and see for themselves. Does the main Kyrian lady have special powers that the other Kyrians or the Archon do not?
We all know what really happened, those who played during WOTLK, that was reality, what’s happening now is “new” reality, and if WOW lasts long enough in 10 more years we might find out that the Jailor wasn’t really a bad guy either just the pawn of whoever the current rewritten big bad is.
They might’ve pulled Arthas’ soul back in Wrath, but time works differently it the Shadowlands. So it might not have actually been until sometime in Legion in the living world before they threw him into the Maw. This seems like a strong contender for what broke the mechanism of death. Especially given the speech the Archon gave.