Tom Brady and Rob Gronkowski could go start a new league and take all the players with them. But they would be playing for the New England Regulars or the Boston Minutemen. I could argue that the players would eventually win out -- that the fan base would switch from watching scrubs in NFL uniforms to star players on teams with new names (in new stadiums, in many cases). But it's a heavy lift and a huge risk for hundreds of players who worked all their lives just to get to the NFL.
The same is true for the MLB, NBA and NHL. You can't succesfully form a players' league because, at the end of the day, fans root for laundry.
But FIFA ... I don't get why they still exist. They don't own any teams or stadiums. They don't own "world cup" and they don't even control the Laws of the Game (that responsibility falls to the International Football Association Board).
And the logos that they own the trademarks to look like they could have been designed by a 7th grader:
Without FIFA, you can still have the World Cup and the European Championship every four years. Brazil and Germany and England would all still have national teams. The Premier League and La Liga and the Bundesliga would all continue without a hitch (and they could even stop worrying about the 2022 World Cup taking a huge chunk out of their seasons). Many fans of Arsenal and Barcelona and Man-U probably wouldn't even notice if FIFA just disappeared from the face of the earth tomorrow.
Unlike the NFL, which sets up a struggle between the teams and the players, soccer's constant battle is one with the teams, players and countries all aligned against FIFA's mismanagement, corruption and ridiculous sexism.
I don't get it.