It is indeed different than the manga, and holy cow, the MC is still somewhat silent but does he have a personality in the movies! Now that is a boss. Of course I'm a "little" late, but whoever comes across this, definitely watch the anime before the manga. Hell, I don't even know which one now (game or anime) is better to start with. But definitely leave the manga for last. The MC's personality varies differently between anime and manga. In the manga, he's called Arisato Minato. My interpretation is that Minato is like みんなと, which means "with everyone" or something. In the anime, his name is Yuki Makoto. Yuki gives me 雪 vibes (ice cold) as well as 勇気 as well a bit, which means courage. Their personalities are different and so are their destinies*. A bit like how the fate and personality in the game is partly down to the player's choices.

I really am glad to have played this game almost 20 years ago. I'm not gonna lie, the manga is slow and random, but it's still a worth read because of the ending and some of the messages, however it requires you to really know the story (the game etc), to really understand it. In my vision they are all worth it. There are other mangas too about Persona 3, I'm checking some of them, and the MC's personality always change. Which is quite fun! I'll probably check for spin-offs and anything related to Persona 3 in other Personas from the series or prequels etc. And repeating, the 4 anime movies really are fun!

*I might actually be a bit wrong here, but lemme add no more spoilers!