I'm not saying they are going to get knocked out. My bone of contention is why they were favoured in the first place.
Spain in 2010 were a team that had the majority of their players play for a dominant Barcelona. Despite their loss, it made sense not to doubt them since these players had proven themselves at club level and how shown they could play with that pattern. In addition they had a class manager.
For Argentina. The entire basis of them being favourites came as a result of European teams not having dominant and consistent runs in their friendly and nations league games. People seemed to just assume both Brazil and Argentina must be better, despite the fact that part of that run of form for these teams was as a result of not taking games to seriously due to the pile of international fixtures over the last 2-3 years.
On talent, the hype around Brazil is justified. They have a collection of attackers only matched by France, a good spine and a good head coach. They didn't look poor in Russia either and have only gotten better since then. In addition, watching the Copa America games, Brazil seemed far more dominant than Argentina, even during the final. Yet due to a lot of people not watching that game or the tournament, Argentina winning and their run of games prior to the world cup in which they were beating the same Copa America teams mixed in with Estonia and an out of form Italy made people automatically select them.
Looking at the tournament, what makes them a better team than Germany who have Kimmich, Musiala, Sane, Gnabry, Muller, Rudgier etc. What makes them better than Portugal with Ruben Dias, Cancelo, Bruno, Bernardo Silva, Joao Felix, Rafael Leao etc. They have Messi in a team with a midfield that is not as good as their rivals, a central defence that hasn't yet seen the light to play Martinez, average full backs who can't supplement their lack of a midfield, an injury plagued Di Maria and Lauturo. A good team, better than most and with a good path, they have a chance to win the whole thing, yet shouldn't have been considered as on of the top 3 favourites in my opinion.