This is super interesting. As a recent Catholic convert, I have actually found the Catholic Church to be quite supersessionist. The idea that comes to mind is the concept that outside the church there is no salvation. Vatican II certainly made these doctrines less problematic; however, I believe it is still a topic the Catholic Church must continue to work to address. There is certainly a debate surrounding the issue in Catholic theology, and it seems the more traditionalist Catholics remain on the side that God’s covenant with the Jews must necessarily be broken in order to establish the New Covenant.