With a little research, I discovered that the 2024 Carioca championship will not have a prize for the winner, but the clubs will receive a fixed fee
I couldn't find out how much this amount is, but I'm sure that your team Flamengo is the one that receives the most from Rede Globo's broadcasting rights
As far as I know the Carioca championship is widely watched throughout Brazil due to the fact that Flamengo has fans all over the country
So in the case of the Carioca championship, this must be the reason why you see teams focusing more on testing players and new formations, rather than actually trying to win the championship, since the money is already guaranteed, no matter the position they finish in the league
Carioca is not the main one and normally lower league Champion it is in complete discretion to the Football federation.I see this implementation quite common in many countries,in fact where I live now they have put a formula that even in the main league to give a prize only to the top 4 teams as they will play against each other to decide the Champion and Champion will not be the team ending 1st in the standings.Nothing to be surprised here.
In Brazil there are these formats of regional championships, they also guarantee a place for the Copa do Brasil [1], is there this type of championship in your country as well? divided by states, usually at the beginning of each season? In the past, these state championships had much more credibility than they do today.
[1] https://en.wikipedia.org/wiki/Copa_do_Brasil