To be brief lets say the end game is the World or Olympic stage. This easily could be pages of debate and I expect I will probably receive comments asking questions but competing too soon is the number one problem in my opinion.
Simply put if you start wrestling at 5 years old and have much success the odds are you won't make it to college level wrestling. Forget about the world stage because you probably won't be around. Pretty much every athlete is dealing with different types of outside and internal pressure when competing. Those pressures come in the form of other athletes catching up, family pressure, making weight, balancing school, and I can go on.
How long before that wrestler says to himself, "this is just not fun to me any longer?" If you start early then dealing with this pressure naturally begins. Those 5 year old wrestlers by the time they graduate high school have been dealing with it for approximately 15 years.
College begins another level of competing and a whole new level of pressure, the athletes you face are just better. Nothing will ever be easy again at that level, and many just say I'm done leaving the sport.
Those who start in 7th, 8th, even 9th grade are just starting to get competitive and still have a love for wrestling. They are less likely to fizzle out because they have not dealt with the outside and internal influences as long as the 5 year old still trying to keep going. They have the greatest chance of reaching the top level of our sport.
Little kid titles are good for a short confidence boost but that is about all it's worth. Find the boost from other places before putting him in a singlet thinking that is the answer. Wrestling is so different than other sports it's fun, but at the same time not fun if another human being is dominating you.
There are rule breakers to every theory and some will start at 5 and be successful but you can't use them as a guide. I see all these rankings for kids at age 8 nationally and I shake my head because 95% of them will not make it past high school.
Always open to discussion!