There is absolutely no guarantee that all these young French players you listed are going to become good enough to replace the current generation.
I still remember when Germany won the 2017 confederations cup with their B-team. People were waxing lyrical about how great the next German generation was going to be. Who cars if Lahm, Schweinsteiger, Klose, Muller, Ozil, etc... are retiring or in decline? They have so many great young players coming up like Ginter, Kimmich, Meyer, Gnabry, Can, Goretzka, etc... Well, now fast forward a few years and suddenly things don't look so simple anymore.
I am still waiting for Koke, Saul, Isco, and Thiago to take over where Xavi, Iniesta, Busquets and Alonso left off.
Remember when Ousmane Dembele was supposed to be the next big thing?
By far the vast majority of talented youngsters don't turn into elite players. From all those "amazing" young talents
@JPRouve listed (Camavinga, Aouar, Cherki, Mbappé, Upamecano, Konaté, Kouassi, Mejbri, Ikoné) there's a decent change that none of them apart from Mbappe ever become world class.