Not sure whether Antoine Griezmann and Giroud are going to welcome this decision, but Mbappé completely deserves this. He was exceptional during Qatar 2022. And he represents the future for France. What is the point in making someone in their mid-30s the captain? In that case after a few years, again they need to search for the new captain. In case of Mbappé, he is already captaining a very high-quality side (Paris Saint-Germain F.C.). Captaining the French national team is not going to be too much of a challenge for him.
The leadership of team shouldn't be based on only skills or on the pitch performance. Leadership requires some outstanding qualities such as patience, courage, team playing and tolerance. I think Mbappe lacks most of these leadership skills. It is possible that he can learn on the job but for me he is not matured for the headship of the French team. Sometimes he behaves very childish and selfish.
But in terms of influence, Mbappe has it. The striker is one of the best players in the world.He could use his influence to intimidate match officials and make them favor the French team. But I hope other older player will be humble enough to respect him. There is a possibility that there might be division in the French team if he is not effective.
That's somehow expected because after all, Kylian Mbappé is still 24 years old and he's not yet on that phase where he will get matured, and will be ready to lead the team. He still needed more exposures from the games and with a proper guidance, step by step, he will be molded into a much better player that will have the characteristics of being a leader. These things can't be taught overnight, the team needs to believe in him first so that soon enough, Mbappe will be a full package kind of player.
You got the point for leading a team it requires certain qualities of patience, maturity and composure and that comes with experience and age .
No one can question Mbappe performance he is exceptionally good player and his contribution for France is noticeable. He'll definitely become good captain but with time it's too early for this.