I honestly get the impression (after over 150 interviews) that they simply remain umimpressed with themselves.
The unconcerned reaction is my way of telling them, in a nice way, that they have not earned the right to force their way into my memories. I suspect that they want to hear my stories for the entertainment value only. And until I decide that person is worthy of hearing my personal reminisces, there will be silence from me.
I suspect these older veterans are the same as me.