Being the largest denomination does not mean they shaped all Christianity. In fact Christianity was shaped before the Catholics split, in the middle east and Asia Minor with Rome being a fringe player.

Their later innovations were mostly left unadopted by the other half of the church and also caused a new split resulting in major intra-Christian religious wars. In fact since Catholics are merely a plurality and not a majority most Christians reject, frankly an understatement, the defining characteristic of Catholicism, papal infallibility.