I think the missing condition here is "if you liked the talk". Not everyone likes or engages with the same material; I know folks who will effectively check out as soon as the conversation gets too techie, but they will happily sit through hours of (vacuous, to me) "life hacks" and pop-psychology talks.

I do agree that there are people for whom "the speaker circuit" is a job, and you can kinda smell it right from the presentation. But I think their numbers often depend on the type of event.