Quora Historian
A person who thinks they know more than they really do about everything and will give their opinions in a condescending manner as if they could never be wrong. To the average or ill-informed questioner, this person will have lots to say and will seem knowledgeable enough, but people who really know them understand that this person is a phony. Any real expert or accomplished person would make the Quora Historian look like a child, which is what the Quora Historian fears most.
All of these Quora Historians are running around talking about the best running shoes and wind resistant headbands for a 5k, but I don't think a single one of them has broken 20 minutes.