I find this explanation extremely hollow. Most programmers didn't start programming when they were kids. They started when they realized it was a good paycheck.
This is probably partly confirmation basis and partly insufficient data. I doubt every time you meet a fellow developer you ask them how old they were when they first started programming.
I'm 35 and didn't start coding until about four years ago (when I decided to go back to school and switch careers) - there's another dev on my team that started even later, and I know several that never wrote a line of code before college. So yeah we're out there.