We all know about Ancelotti great coaching skills and experience of turning the game around in Madrid's favor with his substitutes in the second half if the match is against them. That's the reason why I wouldn't accept that it was Ancelotti's fault that led to their failure this season because he didn't have expected players on ground which he can use to cause damage on his opponents.
The blame is entirely on the injury storm so Ancelotti or whoever becomes the coach will certainly have a hard time, and the condition occurred at the beginning of the season so it is unethical to only blame one person when the team is not fully ready to face the season but Ancelotti is still able to mix the existing players besides Mbappe performed extraordinarily in his hands and got Pichichi. I am sure Madrid will look much better next season.