The thing with soccer is there’s always other options though. So if people lose interest in the international game they’ll just follow the club leagues instead. Tickets for games in England got too expensive for ordinary fans years ago so a lot of English on the south coast took to following French sides instead. When the higher league clubs started clamping down on the hooligans a lot of them just started following lower league or non-league clubs without the resources to deal with them. It’s not like North America where there are just a small number of cosseted teams competing in a single competition. Soccer is all based on pyramid systems (except in the US of course) and always separated by national boundaries (which is a hard and fast rule, UEFA usually come down hard on any countries trying to unite their domestic competitions).