Every community starts out needing to recruit members, so they tend to be very friendly to newcomers.
After a few years, an insider group of old-timers forms. They get to know each other. They know the rules. They know the history and the legends of the community. And it’s only natural to get little bit irritated when newbies show up who don’t know the rules.
Newbies will show up, make a newbie mistake, like wearing shoes indoors or forgetting to close the toilet lid, and the old-timers will look at each other, roll their eyes, and snort, “Typical!”
At this point, if it’s a normal human community, it will start to feel a little bit unfriendly to outsiders. Insular.
And the newbies will say, “well, gosh, that’s not a very friendly place.”