I think that Brazil played as well as the players of Croatia allowed it with their great game.
In the first half, Brazil could not do anything against Croatia, who played a perfect game and hid the ball from the Brazilian players.
Only when in the second half did the Croatian players get tired and the concentration drop, Brazil finally showed their strength in attack, but not enough to win.
However, during the entire match, it was clear that the players of Croatia matched the players of Brazil very well, and even after the lead of Brazil, it was clear that the match was not decided.
What do you think Brazil's players should have done after taking the lead? Play only in defense, defend desperately and forget about attack? The fans would never forgive them for such a cowardly game and it would not be the real Brazil. It was logical that Brazil could not just defend and that they would try to score the second goal and solve the game, but they failed because of the quality of the Croatian team. Croatia didn't beat Brazil by chance and did not win medals at the last 2 world cups by chance. Whoever calls it luck is underestimating the quality of the Croatian team.
I think Brazil needs a good team spirit and less selfishness in the game much more than a good coach.
That is true, Brazil doesn't have a problem with the quality of their individual players, but Croatia has what Brazil is lacking and Croatia also has some perfect characters like Modric or also Perisic who don't ever stoP giving their best until the very last second. When teams play against Brazil they know that it is about breaking Brazil's mentality and that has happened quite often in recent years. Neymar isn't a leader. They also need players who want to lead when it is not going very well. That is the big difference between someone like Modric and Neymar and I am not sure Brazil has a lot of players who could fill that role.