I believe that Real Madrid will remain strong even with the farewell of Toni Kroos, it is true that it will be difficult to replace him but you will see that it will not be long and the management of Real Madrid will find a valid replacement. For me Real Madrid remains the favourite team to win the next Champions League, they have many champions in the team and a coach who was born to win the Champions League
Replacing him is not something I'm seeing any difficulties with in Madrid, they have had times they played in his absence last season and they still did well so all they will have bro do at this time will be with some adjustments where they are going to see how others are going to fit in rather in the position where he's supposed to be. This isn't undermining the fact that he was a very vital and important part of the team and is even almost irreplaceable, but with Madrid I believe they have gotten to that zenith of strength where almost no players exist will really put them off balance but them been able to make adjustments.
We know that Toni Kroos has had a very important role in midfield and not only that, he has always been the taker of free kicks and corner kicks. The problem with his departure is that Real Madrid doesn't really have a complete player like him and despite other facts Modric can do the same thing, I think next season the player from Croatia will rarely get playing minutes.
So this will create different pressure for other young players to take on that task and here there are several players who are quite good at taking on the task left by Toni Kroos. Like Valverde, Arda Guler or Rodrygo have that ability so I think Ancelotti will continue to monitor the development of these players and take one of them to do that job. But overall, if asked whether Real Madrid will remain safe without Toni Kroos, of course the answer is yes.