I played through 6,7,8,9,10, 13, and 15, and am currently playing through 12. And they all use the same way to build the narrative, the same long-winded mission structures, and exactly the same character relationship building designed to work late-game as well and use the same character arcs and character types, over and over.
Right now in 12, I'm at the beginning, and I just ran around the city heralding Basch in a strange sequence, and I just ran around in the mines, back and forth. The way it uses 2-3 hours to build a tiny story arch they could have used 30 minutes on, is everywhere in Final Fantasy. It's a common design principle. The amount of holes in the story in 12 is absolutely comical, the entire party I'm running around with haven't even asked each other who they are.
Final Fantasy stories are shoddy sci-fi that relies on the player getting attached to the characters in your party. The way they build the party, and how they make the player get attached to these characters, is almost always based on the stereotypical Japanese JRPG method. That involves spending a lot of time with your party during long missions that add one piece to the story. Over the course of many hours, they build a narrative and relationships that start to yield fruit late-game. It's extremely common to use time like this in JRPGs, you see it everywhere, it's an ancient outdated design philosophy.
The problem with this is that you have to come up with ways to do long missions, and almost every Final Fantasy does this by having long-winded mostly boring grind missions, but by the end when the mission is over and the new piece of the story unfolds, you forget about the mediocre shit you did the last hour cause you are excited to see what happens next. For example, I just spent an hour or two fighting bats and insects in a mine. It was as mediocre as you can get. Yet, people don't wanna talk about that stuff when they talk about FF12, even though those sort of missions is the majority of the game.
I have never played one Final Fantasy where at least 30%-40% of the game was not mediocre. And every time fans speak about the game, they always conveniently only mention the big story arcs or the music and completely ignore most of the game they actually played.