I think Brazil was lucky in this, because the football that was presented during all the qualifiers was far below what we are used to seeing from the Brazilian team... even the coach was fired due to pure incompetence and not being able to give the team a style of play... the current Brazilian team is sad to see.
For a team that has won the World Cup five times, the game displayed by the Brazilian team now is even worse than people's expectations of them. Their team simply lacks the characteristics of the Brazilian game that we usually watch. Even the high hopes of people for Vinícius, Rodrygo, and Raphinha just can't bring Brazil to their best performance. Their problems may be more complex than they seem, but if they can't solve these problems and haven't been able to find their playing style, then it is very possible that this World Cup will be their worst performance in history.
The problems go far beyond football: it's more like an evolution of society as a whole. For example, when I was a child, it was common to see kids playing and kicking a ball in the street. Nowadays, with rising violence and the advancement of technology, children are heading in a different direction. Because of this, the chances of discovering another great player have dropped drastically.
Football schools have become a business focused on money rather than talent. There's corruption involving agents who promote mediocre players, and foreign teams often poach kids at a very young age. All of this is making Brazilian football increasingly weak... there are many, many factors involved.