I think this article is making mountains out of mole hills in that the answer is really quite simple: such social interaction based games are simply not palatable to Western audiences and Western publishers. And really, for good reason--all you have to do is look at Japanese dating sims to find a plethora (indeed, a whole genre) of such games. Heck, that's *all* you do in dating sims. (And yes, these *are* games, and yes, some of them are quite complex and well-developed)

Western gamers simply don't identify with mundane because it feels trite and artificial. Even the Sims is really about social climbing and wealth amassing, not simulating real life and all its daily chores. The daily chores in the Sims are simply ludic means towards an achievement end, the ludic challenges you need to meet to reach a goal (if you don't wash the dishes, your environment decays, causing your Sims to under-perform, making reaching that next Career tier or obtaining that new piece of furniture [which in the end itself is just to further the achievement goal] that much more difficult). In other words, working to become friends with that one girl purely for the sake of being friends with that one girl just isn't all that rewarding.

And this actually goes for dialogue in games as well; most dialogues in games aren't about the content of the dialogues so much as they are about obtaining ludic consequences. The very few examples in which the dialogue is there purely for the sake of its content (an easy example: certain joke dialogue options in Sam and Max) are used quite sparsely because their reward value is quickly exhausted and they don't serve a ludic purpose, which in the worst case can be confusing or even frustrating to players used to cause and effect. This is why the latest Sam and Max games only work episodically and why they don't have much replay value; you'll laugh the first few times you get Bosco to act stupidly by asking if he has a certain item for sale, but it loses its novelty rather fast.

So really, basically two things: not conducive to (at least Western) player identification, and not conducive to replay value (with extremely few exceptions like Façade, or Alter Ego even, which are not really practical for implementation on an 8 hour game scale). It's not about maturity of games; its about what works interactively, and interaction requires that the player is actually motivated and interested in interacting.