I’m one of the biggest USMNT and USWNT fans on here, and I think that you make some good points. But there is an undeniable “big event” aspect to World Cups that don’t really make those TV ratings an accurate measure of fan interest, IMO. Fox said they had 20 million viewers for the 2019 Women’s final and the men got 21.6 million for their knockout round defeat to Belgium in 2014. The Olympics also draws massive TV ratings, but I wouldn’t say that means people are huge fans of swimming, track and field, gymnastics etc. People like the Olympics because it’s a big event with some good natured patriotism mixed in.
My earlier point was that if you watched the 2002 Men’s World Cup (the best performance ever by the USMNT) and fell in love with that team, you had very few options to watch the stars of that squad after the tournament. Brian McBride went on to have a loan spell with Everton and then began his run at Fulham. Claudio Reyna was in England playing for Sunderland and Man City. John O’Brien was at Ajax. Apart from catching whatever MLS game might have featured somebody from that team, the guys who played in Europe were out of sight, out of mind.
Now, I can watch McKennie at Juve, and Tyler Adams, Gio Reyna, John Brooks, Josh Sargent, Chris Richards in the Bundesliga all on ESPN+. Pulisic (if he ever gets to play again) is easy to catch with NBC’s Premier League coverage. I just think that anybody who gets hooked by the National Team these days is much more likely to become a fan of the sport in general because they can now watch US players play for clubs in Europe. I’m a Fulham fan because I started to seek out Fulham matches when Dempsey was there and they actually were available on broadcast TV sporadically. Add in the fact that I learned that guys like McBride and Bocanegra called Fulham home for a while and they quickly became my club team. Now I’m engrossed in Fulham’s fight to stay in the Premier League and my interest has very little to do with Americans who play there.