The top youth coaches also don’t go to the US and I would say that players preferring the US are in the vast minority and rarely stay there.
Infrastructure includes coaching and development to me and the US just doesn’t have that.
But you’re wrong, they do. There are plenty of high level youth coaches around the world, mostly Europe, that have come to the USA.
Here are some examples
LA Galaxy: Technical Director rain the Mexican National Team Youth Program
Chicago Fire: Technical Director had the same position at FC Basel for close to ten years. Head coach was the coach of FC Basel for two seasons, and then the coach of the US U17 team. Their previous coach was the coach of Serbia’s best generation of youth players in leading them to a U20 World Cup tittle.
Philadelphia Union: Technical director oversaw the RB Salzburg academy for six years, and prior to that held the same position at Hoffenheim. He replaced a guy that worked at AZ Alkmaar and NAC Breda in similar capacity.
FC Dallas: Sporting Director worked in similar capacity at Grêmio and Santos, including when Neymar was at Santos.
Barcelona runs their own academy in Arizona, which they staff with their trained employees from their operation in Spain.
The director of youth development for MLS ran the academy at Le Havre when they produced Pogba, Mahrez, B. Mendy, Payet, Mandanda, Diarra.
And then there are some coaches like Schelotto or Martino that came to MLS. Schelotto left Boca Juniors for LA Galaxy. Martino left the Argentine National Team for Atlanta United before recently leaving for the Mexican National Team. The two best coaches in the Mexican League in recent years, Matias Almeyda and Diego Alonso, both came for MLS and coach for San Jose and Miami, respectively.
These are only examples off the top of my head. To claim the USA doesn’t have good coaches and development staff is ridiculous. There have been plenty of very high profile coaches, directors, staff who either currently work in the USA or did.
I don’t know what you mean by including development as part of infrastructure. Isn’t development a byproduct of the many components of infrastructure?