The net contribution of Christianity to the improvement of Europeans' quality of life during the 20th century was positive.
Christian buildings were a net positive factor.
Christian customs were a net positive factor.
Churches were active to overcome the great tragedies of European live in the 20th century.
Christian institutions were harming the lives of Europeans.
Christian theology was negative for Europeans.
It was the advances of science and technology that made life better for Europeans in the 20th century, not Christianity. In fact, Christianity made life much worse for European Jews in the 20th century as it gave precedence for Antisemitism.