Yes, the best most often start early. But unlike math and physics, disciplines like biomedical research are very resource intensive which leads to older talent as well. My BS was in physics, and I was coding for peer-reviewed research just over a year into my undergrad. In biotech, things are very different. It's typical for investigations that culminate in a scientific paper to take a couple of years and hundreds of thousands of dollars. We've had Seimen's Foundation Award winning high school students come out of our own lab, but these students aren't setting the course of the investigation. We don't have the money and they don't have the time. These students generally flesh out one aspect of an existing investigation. They do great work, but it would be extremely difficult for them to take a study from concept to completion.

I thought my PhD research was fantastic. It was good, but geez could I have wasted YCR's money at that point. :)