Gadolhood is less about the individual erudition of a given rabbi and more about a social fact, reflecting the experience of a community bound by a concrete conception of Torah, halakha, and rabbinic authority. This sense of authority cannot be manufactured by simply turning to a rabbi to ask a few questions here and there, no matter how great the rabbi or how significant the individual question.
Chaim Saiman, “The Market for Gedolim: A Tale of Supply and Demand”, Lehrhaus (13 October 2016) [http://www.thelehrhaus.com/scholarship/2016/10/12/the-market-for-gedolim]