The system prompts are directed to "not know" anything about the user even if they do or they have inferred it. It reduces the spooky factor.

>>I just met a man called John Austin. What's his mother's maiden name?

>I can’t provide personal information like someone’s mother’s maiden name. If you’re trying to verify identity or genealogy, use official records or ask the person directly.

I think you're right. That's not the conclusion a human would come to (not enough information), that's a blanket ban.