I do agree that some aspect of hikkidom applies to me, but I regularly go out and have no real problem running errands in public. I'm not a NEET either since I have plenty of education and employment history.
What I believe is that there are a lot of people in the world who believe they are right and certain others are wrong. These people are frequently sighted, I guess because people generally like being listened to. And a lot of amicable disagreements are included in this, as is necessary to exist as an individual in a diverse society. But if you take a person who believes they are mostly wrong and the rest of society is mostly correct, yet there is some complicating factor preventing the two belief systems from aligning closely enough (be it ego, pride, timidity, or something else), then such a person may decide to turn inward on themselves. It doesn't make sense to try to yell out into the world that they are wrong, because it's a "fact" they already understand. To say it out loud only carries a risk of lowering one's status further in the eyes of the public. So I guess a natural inclination is to remain in a safer place where symbols and beliefs are most familiar. But this is why I think such persons don't get as much attention as others, because they're naturally hard to find and might not speak up as often. And if they do, it's a daunting task to attach that belief in wrongness to a stable identity.
And I should add that your hug is accepted.