the issue is that players in other countries are allowed to go to sport specific programs and dont have to go through the facade that is college basketball where top players go to a uni play30 or so games and are out. aau is not a credible alternative either everyone knows that. basically every sport in the world is treated like this (with the exception of the nfl where no one outside the us really plays)
i do know that soccer in this country is trying to put together programs similar to the way it works in other countries but it is slow to take off and can be very costly for the parents. my cousin is going into his junior year at a hs in arizona, and was all state last year. he has played with the real salt lake junior team in the past and has been invited this upcoming year to go full time to their academy, The issue is that he would then have to leave his school team (that just won their first state title in school history) and move 4 hours away, attend a hs (where he would not play) and then live in the facilities . Both he and his parents are torn about the decision as the focus on academics really is not there at all. He is a solid student and some great schools have already begun to express interest. He also enjoys the high school experience. This is a decision many top athletes in most sports would have to make should the us become more similar to the rest of the world when it comes to developing top tier athletes.