It's just your imagination. There are plenty of people that fit whatever demographic you want to place them in, and plenty that don't.
For example, have you noticed that most world leaders are older men? The older a man gets the more likely he is to suffer from male pattern baldness. There are plenty that don't (Bill Clinton didn't/doesn't much for example), but that means nothing. Older men are more likely to have male pattern baldness = world leaders are generally older men.
You might as well say "Have you ever noticed that many world leaders have grey hair or are greying?" It's the same thing. People get older, the older you are the more likely you are to sufer from male pattern baldness (or get grey hair). That's it. That's all it means.