People always will talk to you about anything they know a lot about.
You can approach any human, of any standing, anywhere on Earth, and if you ask a question that hits them right in their knowledge center, especially if it is something they don't commonly get to talk about, they will positively engage with you.
I know speaking with absolutes on the internet is a borderline crime, but this is so reliable I think it warrants it.
I know you mentioned it, but I'm going to mention it anyway...
One notable exception to this is the person's work. Which I, personally, am not super inclined to talk about with people even though it comprises the vast majority of my knowledgebase. Maybe I'm projecting, but my guess is that Joe Schmoe isn't going to want to talk about his profession after coming home exhausted. That is, unless he's truly found his calling.
This is why a lot of "how to get people to like you" advice is really just "ask them lots of questions"
You ask enough questions about different topics and you'll get a positive reaction probably