From the very first episode of Game of Thrones, the stakes were made clear: You win or you die. Ever since the show began, the question has always been about who would ultimately sit upon the Iron Throne. Robert Baratheon was there when the show started, but it was evident from the first his reign would not last. As Daenerys herself noted, first this one's on top, then that one, and on and on. Warning: Spoilers for Game of Thrones Season 8 follow. But of all the options, almost no one would have foreseen Bran was crowned king on Game of Thrones.
To be fair, I did not say, "Bran is now seated on the Iron Throne." That, after all, would not be the case. That's because there is no Iron Throne. The creation that Aegon made out of the swords of his enemies when he defeated Westeros melted down when the last of his line, Daenerys Targaryen, Mother of Dragons, was killed. She always said she'd break the wheel. Though she probably didn't mean for it to happen this way.
With no Targaryen to take the throne and no throne to sit on anyway, Sam suggested democracy. Not that elections, 24-hour cable channels with horse race coverage, and political ads were going to pop up immediately. These things take time. Instead, Westeros took baby steps towards democracy with a voting council of highborn — a proto-Senate if you will. And then, the council chose Bran.
Not that the highborn of Westeros were very keen on the idea of democracy when Sam first suggested it. He, being an innocent in the game of thrones, wanted the full thing, like the Night's Watch has done, with everyone getting a vote. The laughter was derisive. Suggestions that horses and dogs should get a vote followed. Meanwhile, others assumed this was Tyrion trying to play the game from his prison cell, a plan that they would vote for him to be king.
But Tyrion was done trying play a long time ago. In a way, working for Daenerys broke him of it. And Sansa, who was quietly running the council from her position as the head of the Winterfell delegation, knew it.
Of course, some of those present tried to suggest it could be them, like poor Edmure Tully, but that wasn't going to fly either. In the end, they had to pick someone.
That's when Tyrion suggested Bran. He was, after all, the keeper of the histories of Westeros, and the best story to sell to the smallfolk they've got. He knows the past, and he's smart enough to attempt not to repeat those mistakes. Also, though he is a Stark, he's also the Three-Eyed Raven, which makes him the most unbiased leader one could find among all those who have spent their lives playing this game.
It's a smart move, one worthy of a game player who doesn't want to rule himself, which has always been Tyrion's strong suit. After all, it's a reasonable idea. And even better, Bran would make a good king. All hail Bran The Broken, King of Westeros, Lord of the Six Kingdoms and Protector of the Realm.