Americans are intelligent and can adapt if they are told what to do, but this decision has to come from the top and the bottom. Not only does the head-coach have to implement a different style that works for the physical attributes of American players, the hundreds and thousands of youth and college coaches have to start to implement it too.
What you’re seeing is that the USA’s defensive players just can’t keep up with top players from other countries and the USA also can’t create offensive threats that put the other team in reaction mode.
These videos from the last World Cup in 2014 clearly show the defensive problem that the US has and this was almost the same exact team and same defense used against Trinidad and Tobago that disqualified the USA from the 2018 World Cup. Notice how the same defensive player is clearly out of his league beaten badly on both goals? Also notice that the same USA midfielder lost lost the ball to lead to the other team scoring on both occasions. If you look at other WC games the same midfielder lost the ball that lead to suffering important goals. If you look at the T&T game nothing is different. Same midfielder losing the ball, after all, as I said it was almost the same exact team as against Belgium.
The same thing happened in the 2006 World Cup when the USA played the Chech Republic. Jan Koller is listed at 6’8″ and makes our defender who is 6’1″ look like a rag doll. (see 3rd video below)
Brazil has won the World Cup more times than any other country and they don’t have any overly big players, surely no giants like Jan Koller, but at the same time they don’t have trouble defeating teams with bigger, stronger players. Why is this? This is because they play to their strengths and they have superior skill and speed. They pass around the other team and they make the other team chase them and tire them out. Then on defense they don’t put themselves in bad positions where they are forced to defend 1-on-1 in huge size-mismatches. They play defense as a unit. It’s called teamwork and they play it on a level that is unknown in the USA, so far.
Why can’t US Soccer analyze these games and see this and fix it? You know that teams like Brazil and Germany would fix this problem and those players would be under huge criticism and perhaps the guilty players would have played their last game for the national team. But that’s what separates the top teams from the bottom-feeders.
See for yourself in the videos below.
https://www.youtube.com/watch?v=O9Q2WPLB6OI
https://www.youtube.com/watch?v=TahrcHAMTJQ
https://www.youtube.com/watch?v=5Gg-5DBpiPM