One of my favorite survival games is Zombie Exodus, done by one guy. It's probably the most responsive game I've played recently. It's also only text and pictures. That's why Zombie Exodus can actually alter its world, cast, and story in response to player action. All it costs is time and text. The guy writing it doesn't have to come up triple-A quality animations, art, and VA for each potential branch. He doesn't have to pay people to create that stuff. This is also why modders can create so much for the game, with apparently so little.
EDIT: Sorry if I come off a bit touchy about this stuff. Absolutely nothing against indie game designers or modders; they do awesome work. But I have a few friends who work for large studios, and sometimes I feel like all they get is "Why didn't you include everything we want?" They do work their butts off. But budgeting is a different beast if you work at a studio like Sony or EA or Riot, and nine times out of ten, budget is the reason why something couldn't be done.
I realize that a lot of indies can do so much because they're working with so little, so changing something doesn't cost very much. (I went on a whole tangent about that before realizing it's unnecessary and cutting it.) But that's also precisely my point. Did we really need two voice actors for both genders? Did we really need the Hissing Wastes, the Forbidden Oasis, the Emerald Graves? Did BioWare really have to invest time and resources into luxuries like that, when they could've better refined what's already there? As you said, these games are so reactive because they have low graphics, or no voice acting. Some people qualify that as a negative, but it makes me ask - why have voice acting? Why have high-fidelity graphics? Would a stylized route work better? Would a voiceless protagonist work better? Are the things we obsess over, like graphics fidelity or open-world exploration, really needed to make an enjoyable experience for the player? Why constrain yourself like that, when you have so many resources and so much manpower, when you could make something incredible if you just stepped back and re-assessed what a game needs to be good?
Like - if we cut the Emerald Graves, that could've been another quest in the Mage-Templar plotline. If we cut even half of the Hinterlands, that could've been more companion interaction. If we cut the second voice actress, that could've been more lines for Lavellan, more expansion on her backstory, more depth in her romance with Solas (And probably the others, too.) It baffles me that people praise a decision like that - having voice acting at all severely limits your options to begin with, having four for the most chatty character in the game seems pointlessly excessive. And it makes me wonder - was that really needed? Wasn't there something better we could've done with the resources poured into that?
I know it's not the fault of people like Gaider or Weekes or - or random EA animator #219. I'm not trying to blame them, or undermine the work they do - I know they're only doing what their boss allows them to, and that they probably work themselves to the bone doing it. But it's so frustrating to see larger developers - developers who could be making this era's Planescape: Torment, or Baldur's Gate, or VtM:Bloodlines - waste on pointless gimmicks, while a single person can make a great game by themselves simply by cutting all the crap they don't need.
(And for the record, I don't bear much love for indies either, because that's a scene with it's own mess of problems. But at least they're trying something new, even if it's because their lack of resources forces them to.)