“Responses to questions range from "I don't know, I was just told" to "Let me get back to you"”

I assumed you meant that this created a sense of reflection in the requester as to the value of their ask.

Yeah I can see that now, but for me "I don't know, I was just told" = "Don't know, don't care" and "Let me get back to you" = "I am ending this line of discussion. Don't bring it up again".

If there's a sense of reflection in the requester, it doesn't survive past the end of conversation with me.