2024, thanks for the post.
Agreed, it's a funnel and everyone eventually hits a plateau.
Still, it's good to be able to evaluate current state in context in order to level set expectations or understand what needs to change if you want to continue.
I think you missed the whole point of the graph (which I thought was brilliant). Based on data when they are 14, it is hard to level set expectations cause you don't know the path he is on (or maybe I missed the point of the graph ).
Your son seems like a very solid player. It seems like he enjoys working hard at getting better too, which is a huge plus. I think what most people are trying to tell you is..... Now it is time for Dad to sit back, enjoy watching his son play and quit trying to compare his results to others at his age.
Good luck to him in his freshman season!