Once -- once! -- I was contacted by a domain expert looking for someone else to discuss some arcane tech issue (he was trying to decide if he should commit to a new display technology for their next gen design, or if it was too risky. I didn't make any decision for him or anything, just discussed the issues with him).
Typically the questions I get are from people who aren't really sure about the right question to even ask, typically in marketing or corporate strategy, and typically mid level (not new hires but not the VPs or senior directors either). They always have a particular question they want answered but don't even know enough to phrase it properly ("we're looking into strategic direction for our next level offering and our teams are recommending either writing it in C++ or using the blockchain" -- not an actual question!)
This actually makes sense. If they understood a bit about they domain they would already have contacts, hopefully ones they trusted, to help them decide. The kinds of people who pay (well, get their company to pay) to "speak to an expert" are not idiots, merely domain-ignorant and smart enough to know so. So what I end up giving is a kind of off-the-cuff interactive survey white paper to someone who hopes I don't know who they actually are (well, where they work).