I wouldn’t suggest that Christianized culture is necessarily superior, but I’m also not completely sure that every culture necessarily has the same value, and is equally worth preserving
This is not saying that cultures shouldn’t evolve, adapt, and embrace changing environments, but rather that it is probably a disservice to humanity for one culture to informatically infiltrate and destroy another without an appropriate contest that would establish a hierarchy of fitness. Even then, what kind of fitness? What is a fair contest? Etc etc etc.
Best just to let it be, and let them work out their best way forward.