At the youth level, U17 and U20, there is no reason why the US should not do better. In fact, in the last U17 cycle leading to the India World Cup, a few weeks before the WC the US defeated and tied Spain in two games, defeated Germany and defeated Japan. The US team were playing great soccer, because their coach had the correct idea of treating the ball with respect, being patient and control possession as much as possible. It took her 4 camps to select a team and a few more camps leading to the WC to play that way, but by the end of the preparation she got them to play correctly. So the players, at least at the youth level, do exist.
It is a different story at the senior level. Several countries like Spain (France, Germany, England), that have the size or are smaller than California and have a similar or larger population than California, have better professional leagues (sometimes 2 professional leagues). Think about that, imagine California having a professional league of 16-18 teams, with at least 3 teams being able to wipe the floor with any NWSL team. In these countries (sadly for the countries), soccer takes an amazing amount of funding and time resources. They have crazy know-how and infrastructures developed for men, and within a few years they have made them available to women soccer. The level of coaching and the number of coaches, the know-how, are just not comparable and will never be even close.
To start fixing this, teams in the NWSL should be playing much better. They have the money and they should invest it better (better coaching, hiring players not because of past commercial appeal?). Whoever watched Portland vs NC last Sunday (1st and 2nd teams in the NWSL table), after watching Spain vs England the same day, understand that these teams are playing different games. In addition, little by little, more players that think that the pro path is better for them than college, will continue moving younger to the NWSL; some will go to Europe, etc. US domination is over, instead the US will have a good chance of doing well or even winning a WC every now and then.