Your prediction has a high odd of coming true because in Laliga I don't see any club that her strength is up to that of Real Madrid. Currently Real Madrid is the club that has the best form and they will keep the form for long because Mbappe and the rest players will play for long in the club.
Mbappe is in a learning process and coming to Re Madrid will assist him achieve his best in football because most great players that played in Real Madrid improved themselves in Madrid and also benefited from the club by their outstanding performance. Playing with your seniors and having a good coach will have an impact on Mbappe.
We should not be too ambitious even though we believe that Real Madrid will be stronger when Mbappe arrives, but there is no guarantee of that.Mbappe is in a learning process and coming to Re Madrid will assist him achieve his best in football because most great players that played in Real Madrid improved themselves in Madrid and also benefited from the club by their outstanding performance. Playing with your seniors and having a good coach will have an impact on Mbappe.
Now just look at which clubs Mbappe has experience in and we will only look at Monaco and PSG which were Mbappe's previous homes and only with PSG was he able to achieve big scoring success in every season.
I don't doubt Mbappe but we just shouldn't overdo it because the competition in LaLiga will still be very strong because there are still Girona and Barcelona who will give Real Madrid difficulties.
Believe me, there are always unexpected events that cause the strongest club to experience big problems with its performance.
It is true that there is no guarantee of success as expected, but there is feeling of confidence that Real Madrid will find it much easier, I not fanatical fan of just one football team but I admit that Real Madrid will be very strong team.
Talking about La Liga competition which will still be very fierce is true, but to say that Barcelona is one of the team that makes it difficult for Real Madrid to win the title is not completely correct statement, I sure that next season Barcelona will not be able to play very well.
But for Gurona or Atletico Madrid, they are two teams that can play very well and make things difficult for Real Madrid, but still here, Real Madrid is the favorite with very big chance of defending the title again.