I completely agree with you. Because the first match can never determine the outcome of the entire season. Those who are consistent will probably win. I can give you a real example of this. Argentina started very badly in the last World Cup. Many people made very bad comments about Argentina. But Argentina played very well in their subsequent matches and they won every match and took the trophy. So we can never determine who will win by watching one match. One match can be bad, so there is no guarantee that they will do badly in every match.
Yes, you can never tell how a team will perform in the entire season by looking at the performance of just one or two matches. In this case, you gave a good example, Argentina was defeated by Saudi Arabia by a large margin in the 2022 World Cup, although that defeat really caused a lot of criticism about the Argentine team in the football world, but from the following matches to the World Cup final, Argentina performed excellently and they won the World Cup trophy. Maybe now some strong teams are not able to perform as well as expected, but when they are well set, it will be seen that they are performing consistently until the end of the season and they are very positive about winning the league title. But this much we can say for sure that this season there will be a very tough competition between Barcelona and Real Madrid to win the league title.