I’ve been reading Rodney Stark’s account of the rise of Christianity in the Roman Empire from s marginal persecuted sect to the official state religion.
Ideas matter.
There is no question that it was Christian clerics who were responsible for preserving Western civilization after Rome fell. The ancient literature — and indeed literacy itself — served as a time capsule to be opened when the Reformation, Renaissance and Enlightenment came.
Otherwise the Dark Ages would have been longer and darker with no history upon which to rebuild.