Kingdom Hearts. The whole story since Birth by Sleep.
Moreso what happens when you don't plan out your story accordingly. So much of it has been just made along the way to see what sticks and what doesn't.
True. And also this stupid shonen tendency to trivialize and nulify death. There are so many great emotional moments with plenty of meaning in KH1, KH2, CoM and Days... But they are forever ruined with the more recent games thanks to Nomura and his wish to bring everyone back and let them have a happy ending.
And in part, this also causes what you mentioned: KH3 story feels like a mess because all of these reunions feel like they are coming out of nowhere. They wanted us to feel happy for the characters... But everything felt so wrong xD
It wouldn't be so much of a problem if we were talking about one character, an exception. But we are talking about a crap ton of characters. Which again ties with your observation: they just kept doing games and creating characters without thinking where the story was going. And when they decided to wrap it up... They just couldn't do it in any decent way.