I spent several years as an Orthodox Christian, and the Catholic Church looks like a modern institution next to it. If a Greek Orthodox from 1000 AD walked into a Greek Orthodox church today, he'd recognize the liturgy and what is taught from the ambo (Orthodox equivalent to the pulpit). Both churches are attempting to preserve a traditional worldview in the face of modern societal changes. Both are losing the battle. Neither will admit defeat, and neither is likely to change. If one does, it'll be the Catholics--the Orthodox have no overarching Pope figure with the authority to force change.