If unusual characteristic "X" is important to you, you probably gravitate towards coworkers and friends who are good at X, or striving to improve themselves in

If unusual characteristic "X" is important to you, you probably gravitate towards coworkers and friends who are good at X, or striving to improve themselves in X, or at least respect X --- basically, people who can damp the broader culture's relative indifference or hostility to X rather than amplify it. In contrast, people do not get to filter their extended family network for X. A given person's extended family is likely to be pretty average (for whatever country/city/neighbourhood they're from) in terms of X, respect for X, etc. Perhaps some cousin somewhere is also an outlier on X, but that cousin will have only a little influence on the signal being sent by your extended family as a whole, and you might not even figure out who that cousin is. If you were born into a whole clan of people who are above average on whatever X you find most important, well then by definition you're not in an average situation --- you hit the jackpot when you were born, and many people envy you.