Is everyone else finding this to be true too? That would be really disappointing. Facial expressions was always one of FFX's biggest strengths.
Even if you didn't like the game's characters or story, I don't know anyone couldn't be in awe in how much feeling they tried to put into the game. Scenes like the one where Yuna wakes up with bed hair and the characters poke fun at it and laugh together make it obvious that they really really cared and wanted that to transfer over to the gamer.
The laughing scene is another one. I honestly think it's incredibly cute, I like it more each time I see it, it never fails to make me smile, and it is one of my favorite scenes of any RPG. Maybe this is something that a lot of people didn't realize when they were little kids playing it but the fake laughing is supposed to sound stupid, of course, duh. The other characters look at them like they're stupid. And when they start really laughing at how ridiculous they sound, it does come off as a genuine laugh. It's a sweet way to build their relationship and show how comfortable they're becoming around each other. It's all the more heartwarming when you realize that it started because Yuna was trying to break Tidus was out of his depression. It was one of his few pouty Cloud/Squall/Lightning moments in the game and Yuna was able to immediately fix him.