Your observation is false and easily proven so.
Most of the world is not Christian.
Civilization was maintained for thousands of years before the small Jewish and Christian minority even learned to write.
But thanks for further proving my point.
Certainly, other civilizations exist, before and elsewhere, but what proof do we have to demonstrate that other systems would have produced a comparable outcomes: in terms of progress, human development, etc.?
And could they sustain themselves? Many cultures and religions have failed, been out competed, overrun, or collapsed.
You’re free to assume you can create a better society on other principles. I will urge modesty, and refer you to Chesterton’s fence.