I didn't vomit in disgust at Trahearne as some did, but his crime is twofold:
1. He stops the story being about the character and it becomes about him instead
2. He's just so insanely boring... people don't take to him. He's just this random dull git who comes along and nicks your story. It's all the worse because they actually made some good characters for the Order storylines.
As for him 'saying' it is your story- that means nothing, and it is part of a 'show, don't tell' failure on ANet's part, where they often say things are happening that become contradicted by what you can actually see and experience happening- which is one of those things I can write a lot about. The truth is, you just become a soldier in his army, and it is him that is the essential part of it all. It doesn't matter what he says is so. Defeating Zhaitan needs him, not you. I played the missions, but it wasn't about things happening to me any more, and that's not a 'personal' storyline at all.
It's not even vaguely ridiculous that the end of a single player storyline should be able to be done... single player. It doesn't have to be literally solo- you can be at the head of an army. That's what they do anyway. The fact you have to do it with four others makes no difference in that equation at all, because you don't fight him man to man; you are manning an airship. From which, incidentally, you could kill him solo.
And what are you doing in that final 'personal' story step? Just playing support to Destiny's Edge- who are all bloody useless in-game anyway. This is 'show, don't tell' again. We are told that DE are the mighty heroes who could take out a dragon by themselves, but in fact they are worse than every single player you ever team with. What I see trumps what I am told. And because it s a group instance, there's a 4/5 chance that you don't even show up in the cutscenes, and the group leader gets to be the on finishing the story.
There is nothing about that final story step that in any way thematically connected to the rest of the storyline (which effectively ends twice- once on the final Trahearne mission, and then once more in that Dungeon), and it has become a barrier that has alienated players from the game- and quite rightly. A huge cock up on ANet's part. Forcing people to group to finish something that was meant to be able to be played alone is ridiculous in of itself, and that;s before you add a. the practical difficulties of finding a group that wants to do it, at a time when the Dungeon is actually open to play and b. the technical difficulties which mean on many servers the Dungeon is permanently closed anyway.
(And the Zhaitan fight itself is absolutely god-awful! He doesn't fight back. He sits on a tower being killed. You literally just press a button repeatedly to shoot him until he dies. I thought he was bugged, but no, apparently, that's how they built him. He's the worse end game boss I ever fought, if you can call that fighting.).
No, all in all, the personal storyline part of GW2 missed its mark- and as I say, dev response indicates that they appreciate that. I doubt we'll see these issues happen again, though I also doubt that real persistence will ever come. It doesn't kill the game because it's much bigger than the storyline (in fact, ironically, it gives a better story just by exploring the world and interacting with it than it does by actually trying to tell one), but it's still a shame, and as I say it's removed any interest my friends had.