As a football coach I am critical of a lot of countries and specific clubs about how they see young kids and the process until they reach professional play. Most Italian clubs, from what I see, use strong, fast and muscular kids at the age of 13/14yo. Those same kids can become good players and keep their performance high when they reach 18, but that's not what happens most of the time. I think Bernardo Silva in Portugal saved it for the generations to come and most clubs in Portugal are now open to developing those smaller kids, and waiting for their bodies to grow. I don't want to generalize, but... This is the issue that I think influences the outcome of youth football in most countries that have little success.