Yeah, but in the show, which is the thing we are talking about, Jon has done almost none of that, except the last, which really only shows that Jon paid attention in his lessons and to his fellow man. There is no evidence that Jon has this great political know-how about the North. I'm not gonna buy that based on what they've shown me. Most of the maneuvering in the show is done by Davos, Littlefinger, and Lyanna as far as I remember, who either know how to politick or are a Northerner who have lived through the last couple of hellish years. I could be wrong, I never rewatched S6. But in the show, his experiences does come from the Wall and the Wildlings. I'm not saying it as bad thing either, especially considering how he got a grasp on the Wildlings and how to handle them fairly quickly. The Wall storyline was a mess, so I don't hold that negatively or positively against him.
As far as the rest of your quote, that was only what I recalled D&D, Sophie, Kit and others saying at the end of the finale. I have no opinion on it either way, since most of it talks about how Sansa feels and not always what is absolutely true and shown on our TVs. Jon seems to have great respect for Sansa, Sansa less for Jon in the beginning but there at the end. Next season is apparently going to trash this for unnecessary conflict, so OK show.
Outside of all that, I've never thought that they ever meant to portray Sansa as smart and Jon as dumb, or that they ever sacrificed Jon's development for Sansa's, or ever portrayed either one as unequal to the other. They had the siblings talk, and discuss things, and yes, argue, because Jon was frustrated and depressed and Sansa was mistrustful of everyone (she doesn't like Tormund, now she's not sure of Davos, oh wait there's Littlefinger, she doesn't think Jon can protect her) and terrified. I liked that they had different methods of doing things because of their own experiences and those methods clashed with each other, even though I thought at several points that both characters should be smarter than this. But there are very few conversations I remember that had Sansa bring up her complaints and then not have Jon either get to bring up his own points or refute her own (the much maligned 6x09 conversation, which has Sansa pleading and then Jon basically demanding an option better than his that she can't/won't give, is my favorite example of this). JMO, please.
And also, even if they did sacrifice, it would not be the fault of Sansa the character, but the writers.
I think that Jon is a great leader of men, or very much can be. I think he 'deserves' to be King in the North more than Sansa does Queen as he has more experience actually leading, but I really can't imagine either of them genuinely wanting it, because Jesus what a prize that is not. Sophie can talk about Sansa getting power all the wants, and I can see where she's coming from for sure, especially in scenes with Littlefinger, the show has shown me that Sansa primarily wants to be safe and go home. And vengeance, I guess. Which she has accomplished. Now Sophie says Sansa wants to create a safe haven, which is more in line with my own viewpoint so woo, but we'll see how that works out for her if she lets Littlefinger lurk around.
That quote about Dondarrion is fantastic and I can't believe I never even thought of 'fire wight.'