Actually, this technology has been around and has had lots of research put into it for decades under “Interactive Digital Narrative (IDN)” and “Interactive Storytelling (IS)”. In fact Facade itself was an IS experiment. There have been a lot of those over the years.
I’m not so convinced about that. Have a look at Elan Ruskin? from Valve’s talk about their experimental system that produced “Two robots one wrench” (I know, groan). Their system seemed pretty easy to use for their writers at least.
The point is that for the most part the hurdles are 1) No commercial interest and 2) See hurdle 1 >:)
Ok, that and having a decent animation budget etc.
Weirdly, I was expecting Ken Levine to have produced something in this area by now, given he took his company off to have a look at this sort of thing. But haven’t heard anything recently. Which is a bit sad.
So TLDR: This isn’t really a technical problem more a commercial one.