I'd crudely deduct that being takers/givers in a conversation may be a function of cultural, linguistic, social, and intellectual dimensions coupled with personal, emotional, and ambient states a person is in.
As such there's really very little just one party can do to have a better conversation flowing on their own. So apart from affordance, I think participation seems to also be a key factor and can be seen as "push or pull or slide" aspect of that doorknob.