What's so crushing about the final season of Game of Thrones is that the storyline makes sense... if you set it up. The books go hard on the idea of "Every time a Targaryen is born, the gods flip a coin". Half are brilliant, half go mad.

There's tension the whole book series which path Dany will take. By the end of book five, there's already foreshadowing she's going down the madness path. But the TV shows basically just made her a pure heroine and didn't set up the madness at all. Then they tried to flip seven seasons of Mary Sueing her character in like one rushed episode of She's Evil Now, so obviously nobody bought it. Properly set up, Jon killing a maddened Dany as she's about to take the throne would be an incredible, thematically appropriate way to end the show. It's such a shame the showrunners didn't have the skill to pull that off.

(King Bran is still stupid as hell though)