There are actually probably lots of young millionaires because;
1. due to inflation a million fiat dollars is kinda worthless. To be in the top 1%, you'd actually have to have 10 million dollars.
Wow. You must move in some pretty lofty circles. I'm sure there are plenty of people in the firstest of first world countries who'll never have access to ten thousand dollars in their lifetime and would happily murder someone to get their hands on a million.