It is overly simplistic to say that Argentina lost only because Messi did not play well in the final. He has already scored 8 goals and taken Argentina to the final at the age of 40, which is not an ordinary achievement. Rather, it is an extraordinary achievement. Again, Messi has created many opportunities for the other players of his team to attack.
However, there is no opportunity to underestimate Kane and Dembele just by looking at the results of one knockout match. Kane has scored 6 goals and made one assist in the entire World Cup. Although he is eliminated against France, I will not underestimate him for that.
People can have their opinion to their self, I believe people will say what they want to say, sometimes it's useless to correct people and try to show them because they are going to believe what they want to and not what you have to say. Why even complain Messi didn't play well, alright he didn't do well what about the rest of the players that day, they did a very terrible job, they were aggressive in that match compared to all others they payed on that very day.
I saw a several tweest and the one that caught my attention is that one relate to Mbape and the fans have started using that for campaign already. They said a player that is trophiless in a season can win Balon D'or which was directly pointing fingers to Mbape, he was the best player with Golden booth and yet the teams didn't win any league and in 2013, Ronaldo won a Balon D'or but never had the any trophy, so it's likely he is going to win this one.