So, Jon should have stabbed Dany and took off. That said, Drogon took off with Dany before anyone else showed up as far we know. So, they assumed Jon did or Jon confessed.
Ok, so Baratheon took the throne by conquest. He is killed by Cersei who then puts her kids on the throne as if they were Baratheon's. Technically, we could say Gendry was next in Baratheon's line. We could also say that Jon took the throne from Dany by conquest, yet neither of those things were mentioned. Sam had the only good idea about voting. Of course, you saw the disdain for the actual people when most of them laughed.
I guess I need to stop trying to make sense of this since it's over. lol I just feel like they said, "Ok, we have this many episodes to get from point a to point b and accomplish x. What's the quickest way there? We could just do a lot of cool effects and throw a few bones of info in there. It doesn't really have to feel like "Game of Thrones" anymore because there aren't any more books to contradict what we put out there."
Now, I think I'm done.