>>42879014As a kid, you can go to school, do your homework, and then jam games until bed time. You also naturally learn things more easily as a child.
As an adult, you have way more responsibilities that hinder your ability to play games for hours on end. Adult-life is also stressful, and so are online video games where one wrong move nets you a loss. You're less likely to play long sessions, even if you can, because there's already enough stress in your life that you don't need it from your hobby as well.
tl;dr being an adult is a natural disadvantage
