Brazil were really a big disappointment in last World Cup by not even being able to go beyond the quarter finals. They had technically much stronger players than Croatia but they still couldn't. In my opinion that's because of not having a good management. Tite couldn't bring any significant success to the team despite being the coach for 6 years.
His only achievement is a Copa America trophy in the 2018/2019 season. I don't even have any idea why Brazil board didn't even sack him much before. Maybe the World Cup title would have been achieved with a great squad like this. Ramon Menezes must be the temporary manager now because he was managing the U20 team.
I hope they can find the right coach for themselves to get prepared really strongly for next World Cup.
Sometimes managing a group full of stars can be quite more difficult than what we may imagine, as there are a lot of egos that needs to be fed and this is not possible during the world cup, so this could generate bad chemistry among the players and cause them to underperform at critical moments, while a team like Croatia which also has its own stars but which have the commitment to try to make the best for the team can overcome their deficiencies and play at a higher level than expected due to this attitude.