We know way too many d***ed people.
Through almost the entirety of human history you would be born, live, and die among kin and a few people in your community. Think of 700 years ago. You might know a total of 100 or so people. Meeting new people would be a rarity. A threat, in fact.
I’m an introvert. I’m not shy. I’m not anxious. I just do not require the validation of others and I am not “energized” by being around lots of people. Most folks are this way. I believe we were created, or evolved, to be introverted. Historically, introversion would have protected the community from new folks. New folks don’t represent a good. “New ideas,” “Diversity,” “New Perspectives,” “New Blood,” and the like all represent threats to what before the enlightenment would have been a centuries or even millennia old social order, with a harmony only such a thing could have.
The extrovert welcoming new folks would have put the family unit in danger.
New folks in all endeavors, family, business, politics, citizenry, parties, the donut shop, should all be regarded with suspicion and be granted a grudging probationary period with limited rights while extreme vetting from introverted folks is being done.
After the wariest introvert welcomes that person, consider allowing him in.
Extroverts are dangerous.
In Current Year (TM) North America where everyone moves every 3 years, no one lives near the grandparents, and every place is nearly like every other place, extroversion is rewarded. Extroverted folks are able to assemble a faux community around themselves quickly, they enjoy the process of “getting to know everyone” and generally enjoy the chaos of the modern United States.
When the great simplification comes and the clock strikes midnight, the introverts will have way better opsec because we always have.