Also, we don't see Mary's sin in scripture so I guess we are at a stalemate there.
When Constantine legalized the Catholic Church in Rome and the Latin Vulgate translated the Greek and Hebrew scriptures into Latin, Church doctrine became more standardized with the Bishop of Rome being counted as first among equals. There was a Roman Church since Peter went there and established it but it was an underground illegal church. There were other Churches and at first, the Church of Jerusalem was considered the largest and most influential. Still, there was a basic understanding of doctrine that was agreed upon during the many ecumenical counsels. Once the Church in Rome was legalized, it became the most influential as Latin was spoken throughout the Roman Empire. Even at that point in time doctrine was voted upon in councils where a Bishop from every diocese was represented. So it wasn't Rome who dictated doctrine but with the enormity of Roman and the Latin speaking empire, it became the most influential. The Roman Church had influence since the beginning through the rock St Peter ut the Roman Church didn't dictate doctrine to the other churches but like I said, the council of bishops was united.
I believe two things about that....One is that it was a political move as the Church in the West used Latin and the Church in the East used Greek. The west was united by Rome but the second thing is there was a fundamental difference between the two. The Eastern Church believed that the revelation was already made and there would never be a change to it and the Western Church believed that God would continue to make revelations known to the ChurchBoth groups came from the early Christians who were neither Catholic nor Protestant as Catholicism (as a church) did not yet exist. Not all the Founding Fathers agreed on everything. Thomas Aquinas questioned the Immaculate Conception. The doctrine did not come from Scripture but rather from men's reasoning. I don't believe insight is related to what period in history one lived. It is something given by the Holy Spirit and available to all men in all ages. Living closer to the time of Christ is not a guarantee of truth. There were people like the Gnostics and the Judaizers who were perverting the truth even while the Apostles still lived. The RCC's history is full of competing Popes and changing doctrine. Men who bought and sold offices. Popes used money to buy armies to keep countries from leaving the fold. Popes became mired in politics and war. I don't believe there is/was a monolithic structure called the RCC that dates from the time of the Apostles until today.
The Catholic Church did and still exists. Now since the East-West Schism, we have the Roman Catholic Church and the Orthodox Catholic Church. Both Churches were and remain Cathilic as they accept people of all ethnicities making it the first Catholic or "universal" Church. Before the Universal Church, people's religion was based on their ethnicity. Israelites worshipped one God one way. Then there were the Greek Gods, and the Roman gods, and the Middle Eastern Zoroastrians, the Sumerans had their own Gods, Egypt and China had their own Gods/ The Universal Church accepted people who started off in all of these traditions and was truly a free international Church.
I want to acknowledge your logic but I had the opposite experience that you had. I was raised Protestant and moved into the Catholic fold later in life because I studied theology, and had discussions with my brother who has a degree in theology and a Master of Divinity. The Catholics and theology and theologians seemed to ring more true than the reformers. To me it seemed like the Reformers followed 90% Catholic doctrine but changed what they didn't like and added things they did like which veried between each Reformer
Thank you for putting together a well thought out argument but I still disagree on the Mary issue.....God Bless