Pavel Buchnevich
Drury and Laviolette Must Go
It has almost nothing to do with him.
Player restrictions is the main reason. It's much less restrictive in Germany than Spain, England, Italy or France. And a few have had success there, so that helps for the up and coming players to get scouted. If you are Schalke or Dortmund and you've either sold American players for large fees or are about to, you are definitely willing to bring in a 16 or 18 year old American kid on a free into your academy. You've already had a lot of success doing so. Meanwhile, a club like Atletico Madrid or Liverpool has no success with that.
The German-American players are due to the large US Army presence in Germany as opposed to other European countries, but usually when most people talk about American players in Germany nowadays its about McKennie, Adams, Reyna, Pulisic prior to this season, and not Brooks, Chandler or Johnson.