The Bible says to follow oral tradition too. You do that, right?
Whose oral tradition?
The oral tradition of the apostles was eventually written down for us in a complete Bible.
Only the gnostics believed in a secret knowledge that could only be learned this way.
Before the Bible was complete, the teachings of Christ and the apostles were communicated orally. After the completion of the scriptures their doctrines could be read by the literate and listened to by those who could not read.
You are advocating the exact thing Christ rebuked the religious leaders for during His earthly ministry:
Mark 7:8
“For laying aside the commandment of God, you hold the tradition of men —the washing of pitchers and cups, and many other such things you do.”