I absolutely disagree with that.
On an individual level, Christianity has turned a lot of people's lives around. It doesn't make them perfect ... but it definitely puts them in a better place than they were. The story of Western Civilization is, in large part, a story of redemption -- on-going, gradual, incomplete -- but redemption nevertheless.
It is quite incorrect to state that "redemption" is not of this life and world.
The very life of Jesus is the breaking-in of God into this world, into this life (and directly so, in the case of His disciples).
In Christian theology, the power of "this-world" redemption is granted to the Holy Spirit, Who works in and through human beings.
The New Jerusalem of Rev. 21 is of course the ideal ... but Christianity holds that God is active and engaged in this world, even now: Redemption is a real-time deal, not just an end-times hope.
My post was written from the perspective of a non-believer such as Ms. Rand.
There is no way she would believe in the ongoing redemption of the world you mention.
Western Civilization not only does not seem to presently be undergoing even “on-going, gradual, incomplete” redemption at the present time. It appears to be going in reverse over much of its former area, at least if we use moral standards and belief in Christ as the standard. Most of Europe is essentially post-Christian at this point.