MLS NEXT and ECNL has way too many teams to be pro bound players only. They appear to be more of a league that wants to see the top 10% and see where that 10% lands when physical and mental maturity hits - college or pro. There's nothing wrong with having a top tier only program if it really allows top tier teams to join.
Average U9/u10 players don't know how to cut off angles but the elite ones do

they may not grow up to be elite as others start learning how to handle angles but at that age, they're the top of the class. That's why they play flight 1 at that age. You're right, most kids are not doing it at that age, that's why they should be playing flight 3 like most kids should. Nothing wrong with that until they do start to accelerate. Parents can't seem to understand this. They want their kids labeled as special and elite at u9/u10 or else they quit the sport or find a new team. U9/U10 average kids may be the future elite kids, depending on how their bodies and mind develop. Most 8/9 year olds are not going to show signs of whether they will be a doctor or business entrepreneur yet. A few will and then change their minds later because science or managing people is too difficult. Let the kids play at the appropriate level and don't get sold as "Champions league" when it's actually flight 3 renamed for parents.