I'm an immigrant and all the years in the refuge camp in Germany played soccer. Not official soccer, not a real soccer ball even, but sure did kick a ball around.

Also, on a number of occasions I sneaked in a near by town stadium to watch soccer games. The games between the bakers and the chimney sweeps were a hoot. The bakers in white uniforms had flour in their pockets and the chimney sweeps in black uniforms had soot in theirs. Now and then they would reach in to their pockets and toss a handful of stuff on their opponent. Just a few years after WW-II, the Germans knew how to have fun!

The point is I was very familiar with the game, but have never watched a complete professional game since! I've seen just a handful of games that my grandkids participated in.

So, any claims of correlation between being a soccer fan and length of ancestry tree in US are specious.