I think most of that "natural" ability is still down to practice. Tiny innate differences and advantages push people in certain directions, which means they practice those more (through play, to start with), and pretty quickly there are big apparent differences.
If genetics didn't play a meaningful role in athleticism, we wouldn't have evolved it. But even if that was true at some point in history, that would only be temporary, because without selective pressure, genetic drift would move the population to some point where there was selective pressure.
Obviously environment plays a role, with climate giving kids in California more practice time, or the annual cut-off date in team sports affecting who's in what age group.
On the other hand I am much better at software development than a lot of other people with the same background. It was always easy for me to comprehend things and then I also put in a lot of work.