The Brazilian National team right now is a total mess and in little over 1 year there will be the World Cup: I really struggle to image Ancelotti accepting this type of offer while having only one year to prepare Brazil for the World Cup. If he actually manages Brazil will be after the World Cup, not before, there are just too many risks otherwise.
This rumours have been circulating from a year or so. First it was denied since things went very well with Real Madrid. This season was different and with the struggle of the team to stay stable and the knockout they got in UEFA Champions League then this possibility remains high. Carlo Ancelotti might join the Brazilian national team indeed because after all he already knows directly or indirectly some players there so he will not totally start from the ground. In fact this will help him fix the team faster.
I personally see it as an opportunity to revive Brazil and be a hero.
This Brazil team is quite bad compared to what it used to be but the problem is that no matter how the players are, the Federation and the fans always expect their team to win the World Cup, there are no excuses. If Ancelotti actually accepts this offer I think he must be very clear that his goal is going to be the 2030 World Cup because he needs time, they can't expect him to manage the team for one year and win the competition.