It's okay to not be well versed in a subject outside of one's area of expertise. You can still carry on a conversation and ask engaging questions to have an intelligent conversation. If one is unable to engage in a meaningful manner outside their area of interest/expertise, then that's an entirely different situation. And probably another interesting subject up for discussion if it can be handle delicately an non-hostile.
> ask engaging questions to have an intelligent conversation
Read a book once which outlined 30--40 occupational areas and two or three interesting questions in each of these areas -- to serve as reliable conversation starters.
Found it on my shelves! Closer to 100 main categories! [1]
Random example: Talking to Kitists. Do you fly a traditional or manueverable Kite? How big is it? .. (If maneuverable: How many lines does your kite have?) .. Do you have trouble finding enough open space to fly your kite? .. Have you ever been dragged by your kite? .. Do you anchor your kite, or do you hold onto it. .. Do you fly your kite in competitions? .. Do you do any kite building or kite painting?
[1] By Leil Lownes How to talk to anybody about anything: Breaking the ice with everyone from accountants to zen buddhists 1993
Offhand I am seeing no match on archive.org or Amazon. Worth hunting down. Thanks for the prompt to look for it!
This is fascinating, but it seems like a specialized profession in and of itself to remember all of these questions. Maybe you can look it up a during a bathroom break...
I don't believe it has to be about rote memory or repeating any questions verbatim, necessarily. Rather, as with learning from converstation, from the half-conversations in this book one's imagination and knowledge of another person's perspective will already have been sparked to some degree. That, plus having some hint of what is of open interest in different fields, is part of the value.