Jon Ingold from Inkle has made an interesting presentation on how to write better conversations in games. ( https://www.youtube.com/watch?v=_vRfNtvFVRo&t=1494s )
The problem in game dialogue is that the excitement and drama often gets murdered because there is no real structure. Dialogue keeps getting looped, because the player gets the NPC’s to keep repeating themselves, killing whatever momentum the dialogue might have had. He gives an example from Assassins Creed Odyssey, where the dialogue also has no subtext. The characters say exactly what they mean, there is no meaning behind the lines.
Ingold shows a scene from the movie Bladerunner, here the main character Deckard is a man whose job it is to find rogue artificial people and retire them. He visits the corporation responsible for creating them and ends up in a conversation with Rachel, the niece of the boss. She asks him about their pet owl.
Rachel: Do you like our owl?
Deckard: Is it artificial?
Rachel: Of course.
Deckard: Must be expensive.
The entire point of this conversation is delivered through the subtext. In Bladerunner, real animals do not exist anymore. Instead people with enough money can buy artificial ones. Rachel does not aks Deckard about the owl because she wants to small talk about animal. She is making a iclear point. We are very very rich.
Essentially, Ingold argues that if all of the meaningful interaction is happening in the subtext, then the text itself does not matter that much. That is how we do interactivity. We assign the subtext as a fixed structure that we are not going to give up and in return we give the player variyng text which allows them to feel like they are in the moment and maybe have a little bit of influence along the way.