It is true that there are many factors that can influence an individual's skill level at any given activity. However, this does not mean that Nikhil's original conclusion is wrong. While it is true that some people may have a natural aptitude for something, or that the amount of effort put into honing a craft can play a significant role in skill level, in the end, it is still practice that makes perfect. Those who "show up" for their hobby, again and again, will most likely become the most proficient at it in the long run.
If the "royal fish" of the poker table puts in enough effort and shows up enough times to learn the game, then it stands to reason that their skill level will increase as well. The same goes for the person at yoga class who struggles with boat pose, or the tennis player who has yet to perfect her overhead smash. Nonetheless, these individuals may not yet be perfect; but with enough effort and dedication, they could one day be far better than everyone else at their respective hobbies!
Furthermore, no one needs to be perfect at something to enjoy it! The beauty of a hobby is in its ability to bring people joy regardless of skill level. So don't be too hard on yourself; just go out there and have fun—practice and skill will soon follow!