Then there’s the issue of being sure that those doctrines were allegedly held in the very early church, that they were indeed taught by the apostles, and that they were handed down faithfully and without change or corruption.
Without written records of such beliefs, there’s no way to verify so people are forced to take their church’s word for it.
And looking at how doctrine and theology and rules have changed in the last 2,000 years in Catholicism, I find it improbable that some were passed down that faithfully and without corruption.
Catholicism can’t even decide if priests should be able to get married and how to deal with homosexual sin and pedophilia within the clergy.
WHY would anyone think they could trust any other decisions or teachings they adhere to that are not explicitly stated in Scripture.
Which, for the record, remains unchanged for thousands of years as we have ancient texts that verify its changelessness.
Revelation chapters 1 thru 3.