Yes, you're right, Ancelotti will be coach of Brazil team in the summer 2024, so he'll still have a whole season to win La Liga and possibly another Champions League. ) By the way, there are rumors that Real have already offered Negelsman a place in Real, after Ancelotti's departure, so that he waits for this season and does not sign contracts with other teams. Maybe it's just a rumor, but who knows. )
I thought that if a coach coaches a national team, it doesn't prevent him from coaching a club... I could be wrong, but I think some coaches have coached national teams and clubs at the same time... Although probably for Real Madrid this option is not suitable... I didn't realise Ancelotti would be leaving the club in a year...
Real Madrid would have honor Anceloti and allow him but this is one of the biggest club we are talking about, they need Anceloti more than any national club need him and that's why he himself will take the job by next year. Brazil isn't even his nationality to begin with, there is no point of doing double work. It will even make him concentrate less in Real Madrid if he should manage to club and there wouldn't be time for rest and vacations because literally he would be active during domestic leagues and Champions league and will take over the national when the domestic leagues resume. There is no way for productivity if national teams clash with domestic leagues, it's better that way to quit the club by 2024 before summer time.