Kent is 21, but even though he's young, it seems over for him. He dropped out of college once already. This summer, he took one class and after two weeks he was already failing it. All of us here assume that he dropped out of that course and that he stopped going to college.
It seems that you are missing part of his story. The video you want to watch is "Kent Talks About Having A Learning Disability", if that's uploaded somewhere on Youtube still. In that video, he explains how poorly he did in middle school and high school. He admit that he has poor reading skills, a difficult time understanding the material he was given, which explains why he did so poorly on his tests and received mostly Cs and Ds. He emphasized more than once in his videos that he couldn't pass the final exam in order to graduate from his high school. He mentioned that his school had to give him a waiver so that he could pass.
Kent doesn't really talk normal. I don't think he would be able to hide his quirky characteristics with people who end up talking with him frequently. Kent has a bit of a stutter, has a limited vocabulary, talks too casual by using too much slang and idioms, repeats himself too often and strangely repeats phrases that he hears from his environment, and uses odd language (e.g. "color coordinate"). I've talked to asspies before, and the immediate thing that you notice about one-on-one conversations with them is that it is kind of restrictive. They can't really socialize much outside of their interests, and the focus they have on those interests are intense. That doesn't seem like Kent though. I'd say that you really notice his asspie tendencies when you hear him talking about things that he likes, like all of those recap videos he made about Seattle videos. His fixation on the Space needle is very peculiar. I say the jury is still out whether he has the condition until confirmed by his psychologist, but I wouldn't be surprised if he really does have aspects of the disorder. He said it himself that he was partial diagnosed to having the disorder while in high school.