All of this that you wrote is very exaggerated, the Ancelotti era is not over, it also makes no sense for him to leave Real Madrid just because he did not win the European Champions League this season, and as for the La Liga title, it is still mathematically possible for Real Madrid to win it. Real Madrid achieved a lot with Ancelotti without having spent a lot of money on signings, at least compared to many other teams. His contract ends on June 30, 2026. So it makes no sense for him to leave this season.
Ancelotti has achieved a lot for Real Madrid since he became their head coach so i wonder why anyone will attribute his failure in the champions League as what will prompt his actions to leave the club. Even if he wants to leave the club it won't be on the ground that he failed in the Champions League games and besides, do they expect him to be winning the Champions League trophy all his season at the club?
Now that Real Madrid is out of the Champions League games, they will focus their interest on the La Liga and Barcelona shouldn't drop points if they dream of winning the La Liga because Real Madrid will make sure they keep winning their matches if Barcelona can drop points and they overtake them. Ancelotti cannot leave when his contract hasn't expired, and Real Madrid can even choose to extend his contract when it expires in 2026.