The cutscenes were so poorly directed, shot and voiced that I ended up skipping them when playing, pausing the game then finding the corresponding scene on youtube at 1.5 speed. I was ready to forgive the dumb dialogue - it is Kingdom Hearts after all - but watching a bunch of weird 3d Unity plastic dolls talk at each other instead of with each other (complete with notable dead air between every line of dialogue) was grating to me. Made me really worried for FF7 remake, and was legitimately surprised how human everyone sounded in that game, opposed to this. The voice direction was terrible across the board - prior games' voice acting was much better directed (barring Terra from BBS).
The first scene of this video was a standout in my head, because it was so unlike any other scene. They talk over each other! And as hammy as their performance is, I'll take it over everyone's "dead inside" tone any day, was a fresh of breath air. Upon rewatching it just now, it's not even amazing, but a cutscene that is simply acceptable really stands out when literally every other cutscene in the game is subpar at best.