Are you sure you want to make a claim that DA never let us interact with anyone outside of the group? Because I remember NPCs I could interact with, in pretty much every zone (that's not counting all the other NPCs we've met when doing, say, main quest) - especially those I can recruit as agents, even going as far as deciding their future fate. Those weren't very deep interactions, true, but so far into my TW3 playthorugh that's significantly deeper, save a few sidequests.
The only person I remember having interactions with was that Sutherland guy. Which consisted of simply supporting him and then saving him later. Whose future fate do you decide? What job they'll take? How does this define the IQ?
Outside the main mission (the only one being Wicked Eyes and Hearts) who did we interact with to the point of defining who the IQ is as a person? How does the world change and respond to the IQ based on those interactions? The Judgements? All you do is decide whether to punish a criminal or recruit them. At the most it says you're either nice, gullible, or hard on criminals. Now this could be something to go on if Bioware gave us some sort of follow up on making these choices.
At the most you get some companion disapproval or approval points. The people you recruit don't define who the IQ is as a person. Meeting some random hunter and asking them questions does not define the IQ.
So yeah I stick to my claim.