So is Ancelotti at this point considering both to be used at Real Madrid or one of them? considering they both have shown their quality every time they are given the opportunity to play like you said, Because Real Madrid will not be bad when they have to rely on Luca Modric for another season, because there are many other players who can make Real Madrid strong for next season.
that's not the case. for now a replacement for luca modrid already exists but because Luca modrid is still quite fit and can still be relied on then Federico Valverde and Eduardo Camavinga will be substitutes. Ancelotti needs luca Modrid for next season because his role on the pitch is very important to help attack and be able to turn on a more aggressive game. Real madrid next season seems to be the strongest dominance to win Laliga.
Speaking of stamina, Luka Modric is still quite fit but has decreased from the previous season, and the playing opportunities that Ancelotti has given to Luka Modric have also decreased if look at the appearances of the 36-year-old player from the 20-21 to 21-22 season. But I have no doubt that I will see him again maybe in the next two seasons with Real Madrid, because Modrid has an important role as you said.
Talking about potential La Liga winners next season, maybe I'm a little doubtful, because on the other hand Barcelona as a rival also made changes in Xavi's hands.