I find that with the quantity of dialogue, I tend to observe the opposite trend in a lot of story-driven videogames: many lines will be devoted to elaborating on needless backstory, reducing characters down to walking encyclopedias. Many of these games have a hard time taking advantage of their medium as far as their story goes.

Her touching on the loss of quality in dialogue, not just quantity, seems like the more important problem. To me, meaningful and good dialogue is important - whereas dialogue for the sake of dialogue tends to suck. I'm not saying that everything that comes out of a character's lips needs to be important plot points, but writers and producers should think more about what they're trying to accomplish in their work when a character needs to say something. I think a piece of bad dialogue hurts more than if that character were to say nothing.