Those are special generational players. Countries like France, Spain, Brazil, etc consistently produce world class players and out of those world class players come a handful of special ones like Ronaldo, Messi, Mbappe, Neymar, etc. The reason why is that their country's sports culture, clubs, academies are so refined that they produce a high number of quality footballers. It has little to do with genetics. Greece has somewhat the culture, but the clubs and academies are nowhere near par.