Those who can't reconcile their political beliefs with the doctrine of the Catholic Church need to choose one or the other. Many Democrats have chosen to abandon Catholic doctrine for the sake of their political views. Even worse, they ignorantly demand that the Church bend to their political whims while their views drift like the wind.
If people want a modern church, then they should join a mainline Protestant church, say like, the Episcopal church. The Catholic Church isn’t leading anybody backwards. It the high priests of secular humanism that are doing that. The Church flourished the most during the medievial period which gave us the Renaissance. The Renaissance gave us The Enlightenment. By the 20th century the Church began to decline, which happens to be the bloodiest and brutal period of human history.