You are absolutely right.
My journey to Catholicism was circular. I was born into a devout Catholic family, but as a teen in the 1960’s developed a doubt, bordering on contempt for all authority, school, parents, government and church. For a significant period of time I was an agnostic and believed that I was a Catholic and Christian only by accident of birth. In this time I looked at virtually every religion. I studied the Buddha, I read many of the Upanishads and the Ramayana. I read the Koran, the Book of Mormon, the Book of Moroni and A Perl of Great Price. I read the works of Calvin, Luther, and the writings of Aquinas and Augustine among many, many other works in my search for the truth.
What I concluded was that there were far too many instances in the history of religion in which an individual or class would establish themselves as the intermediary between man and God and required that all communication in both directions went through them. Only they could speak to God and God only spoke to them and in exchange for this there was a price to be paid by man. Often this was in the form of wealth, power, influence, access to women, cattle, the proceeds of sacrifice, palaces, etc. Whether the Buddha, Moses, Mohammed, or Calvin there was little difference in the shake down.
I found the one exception to be Christianity. Jesus preached that no one was denied a personal relationship with God. He preached that all could communicate with God and that no one was excluded except by their own deeds and lack of faith. He asked nothing in return except the two greatest commandments and offered himself up to a horrific death, not for his exhalation and enrichment, but for us.
Jesus also differed in that he did not author an Opus that generations of theological lawyers and priests could manipulate and reinterpret for their own benefit. He gave us a very simple message perfectly summarized in the Beatitudes. He also relied on eye witnesses to spread this to all mankind.
This is why I believe that all that is needed for Christianity and Salvation is completely contained within the Synoptic Gospels. Everything that preceded them was in preparation for Christ and everything that followed them had a single purpose; that was to help to explain them. It was not to add to, extend, modify, reform or revise the Synoptic Gospels. Those who rely on single versus or Paul’s letters to establish or rationalize a position that is not found within the Synoptic Gospels are simply, ignorantly, or intentionally wrong.