The difference premier league and other leagues is the fandom. There is literally nothing else that is different at all, it is clearly the fans are the difference. Because your team could be in league two, and you still support the team you are from. In situations like Bundesliga, or ligue 1, you see top teams, like Bayern and PSG get the most viewers, because they are successful, a team like Lyon, who won so much, ends up losing out and nearly even relegated because as soon as you are not good, you lose fans. Not that many nations in the world, has crazy fans all spread around the board.

City was one of the best in premier league, won 4 times in a row, and they still didn't had the most fans, other teams had great fans, you can go to some 5th division game, and you will see stadium full of fans. You won't see that in any other league.