I don't think anyone on college campuses these days doubts for a second that everything they think/believe is the absolute only truth and that they do indeed know everything. People used to grow out of it. They don't seem to be doing that as well/early as before. If they ever do.
They are very quick to back down from their pronouncements once challenged by someone with more 'status' points, aren't they? If a lefty male is told by a lefty female that he knows nothing about feminism because he hasn't experienced what she's experienced, he backs down and has lost the argument despite however much he has studied or learned. He can't win under the rules they play by. Likewise the female will lose when challenged by a female of color.
And I wonder how much of their experiences are even true. Yesterday I went home to let the dogs out and give them their dinner after we had been gone most of the day. While I was home I filled a water bottle. I pulled out of my driveway and to the 4-way stop on my corner, which is very low-traffic. While I was at the stop sign I raised up my water bottle, closed my eyes, and took a long drink. When I opened them, I was looking right at a teenage girl who was approaching the corner on her way from the neighborhood pool. From the look on her face I would give 10-1 odds that she thinks some dude in his 40s was creeping on her. That's her experience, and if she believes I was staring at her lasciviously, she's dead wrong, but understandably so. On the other hand, maybe I'm wrong and she could see exactly how innocent the exchange was.
The difference is that some people can walk away from experiences like this with a shrug, and for others they are currency in a struggle to demonstrate oppression.