Why did Bran become King?

I have read so many posts here about why Bran become King and a lot of is just very negative due to expectations that was not met by the Fans who I think you are missing something about the theme of this show. Bran is NOT ruling alone, that scene with Tyrion arranging the chairs and the people who showed up that table are his new administration. That scene was there for a reason and it was pretty long. I knew from almost 4 or 5th season that who ever ends up King it wont be either Jon or Danny, those were what many or majority of FANS wished for, but they dismissed the signs and clues and the very core of the story and theme of this show was that it was about shift of power in the chaotic universe.
Those that were in power from the start Robert, Ned Stark, Lanisters, Frays, Boltons, Jon Snow, and Deanrys,, each represents the many aspects and features of power structure; such as strength, deception, claim, justice, ambition, manipulation, ruthlessness, vanity, fear and all of these is bound by the element of FATE. Ned Stark was a man of virtue and yet he was killed for his principles that was echo of how the universe is so chaotic, that had been the core message of this entire show that nothing is certain or they way we want things to be in life. Bran was someone who unlike anyone was not seeking power; and nor did he wanted it but his ability to see the past and see what mistakes caused wars and also having Tyrion at this side along Davos ,Sam, Brieane etc, it is what makes the entire infrastructure of what Bran's administration; to have the support of experience that he needed on his side. I personally always thought Tyrion will end up being King, that was my hope but Bran choosing him for hand is actually made me realize how their pairing is what makes to work, so what you are forgetting that its not just Bran, its a whole package that comes with Bran that fills in the gaps for older experience he may lack to get council from a group of people who are NOT sitting around plotting who to kill or conquer next. All those people we saw around the round table with Tyrion went through hell on this show to know they don't want to repeat of that again and when the Dragon scorched the Iron throne it was a metaphor( just like in the Lord of the Rings when the ring itself got thrown back into fire) that it ended and its new beginning for the 7 kingdoms.