Direct quote 1999
“With games today, the characters are like dolls or puppets, so you can't really get "performances" out of them. You can animate them, and there's the voice actors, but that's it. You can't really get anything subtle. I'd love to be able to convey emotions like that but it's just not possible yet.”
What it documents
In 1999 Kojima explained that in games at the time characters were like dolls or puppets, from which you could not get “performances”: they can be animated and there are voice actors, but nothing more, nothing subtle; he said he would love to be able to convey emotions like that, but it was not possible yet.
Source