I think the big team players are starting to care less about the National league. Being constantly playing matches depresses them physically and mentally for footballers. The fact that earning more advertising revenue and money is more important than the mental and physical condition of the players. At the beginning of the tournament, i wasn't thinking of surprise results, but when i saw the group winners, i changed my mind. The players are not mentally prepared for this tournament in my opinion.
Many players don't feel like playing these matches at all. Of course we see that they give interviews and that they say that they are looking forward to it and that they want to win, but that is simply a moral obligation to the fatherland. Kevin de Bruyne was recently one of the few players to come out publicly saying that he had no appetite for these conference leg matches at all. Now it can be a preparation for the World Cup, but that is a coincidence.