This is the problem: you've invented this scenario. There is a gaping middle ground between what people are describing and your stereotype of what they "must really mean"?
Too many people are too un-self-aware to recognize that their "just a 5-minute question" is being asked because they have not internalized the knowledge, rather than because it's genuinely something that they haven't had an opportunity to learn—too un-self-aware to recognize that this situation is unnecessarily stressful and it's their fault.
Of course this has nothing to say with selfishness or else. It's simply that each Group project their own ideas to the outward world -- so people who like to outreach think other people like that too, while people who doesn't think the inverse. But taking a step back as a third party, we would realize that Group 2 is usually more harmed than benefited.
This is just assumptions though. Too many? Compared to what? Narrators are just as unreliable as anyone; some will be unreasonably opposed to any questions. Complaints aren't all 100% trustworthy. And complainants can also be un-self aware in that when they were more junior, or new, then they also asked questions. They just maybe had people answer them who were more happy to invest in them.