Ancelloti has won almost every major trophy during his time as a coach and maybe a season without a trophy is not a big deal for his reputation. La Liga still has a chance that they can chase as long as they can make a much better performance because when they face El Clasico they can close the gap on Barcelona even though they will still be one point behind Barcelona.
Barcelona will be more focused on preparing for the semi-finals in the Champions League so the coach will definitely make some rotations and if the results are beyond expectations because they will draw in the next match then this scenario can be used well by Real Madrid so they can chase points in the crucial match when the two meet.
Yea it may not be a big deal for Realmadrid to be left without any title this season because of their history in regards to the number of trophy they have won before as you said but it becomes a real bigger deal when a team has all it takes to get what they want but failed in the race for it, Realmadrid is not just our regular teams, we are talking about a team that got most world sophisticated players, personally I must be sincere I expect a whole lot from Realmadrid this season although good teams are faced with obstacles sometimes, may be luck was not on their side this season.
In as much as we assume or think that Barcelona will give more attention to the champions League semi finals which may be right too we should also know that they will not be joking with either the laliga or Copa Del Rey because those competitions are also important after all they add up to the number of those competition they have been able to successfully win, as we know already, laliga is a big deal for them at this stage because of the position they are occupting presently, they won't want to mess things up this time.