@CinderKin nah, not necessarily.
I would assume that a game would recognise certain key word combinations as the correct inputs to progress the story, and everything else would be met either with a "sorry, I don't understand what the hell are you talking about" or a simple -10 affection penality.
At most it could be something along the lines of how AI Dungeon (https://play.aidungeon.io/) uses neural network to respond with what is interpreted as a valid response to user input. But that's just silly.
@Cinderkin@Reimos
It's a pretty minor detail so I don't think it counts as spoilers since it looks like it won't go into detail.
Based on the source novel, the text recognition was very simple in the original game. MC said that it was mostly just generic phrases and "yes" or "no".
So nothing elaborate that would derail the game's plot. I guess it was just to give the player some artificial freedom.
i'm glad they acknowledge her feelings in being forced to apologise for something that's sharply out of her control- it's one of the worst feelings ever.
i genuinely hope she gets to rise above that soon. since most likely the brothers will end up more friends than foes later in the story, i hope they apologise for how they treated her, as well. even if the old girl was super violent and horrible to be around, it's obvious her environment and initial coldness was what drove her to be that way, and that needs to be held accountable even if ultimately it was the girl's own personality that got her dead.