When you say that the community is about exclusion and not inclusion you are actually making a solid point. The community is a sub set in a much larger Venn diagram and apparently it is not just a subset it is actually a very small one too. Since most of the communities are small except for a few that are the exception.
At the end of the day we all maybe part of one or the other community but most of the people are not part of our community. Yet in a social environment we tend to seek support of groups with interests matching ours.
Now here is the weir part - we hope to share our talents inside that group so we may rise to a position of prominence within it. Final aim being that once we rise high enough our voice could be heard by people outside that community. Groups that tend to recognize that may not be very warm but they can be competitive and with a propensity for creating leaders.
This is what a lot of people find difficult here as it isn't 'apparent' who is similar until more investigation is made which requires work/engagement. Going on content alone is difficult because it is only a part of the story and most people mix and match a little.
It is about creating influence and recognition for ones own position I guess.