Your personal conclusion is welcomed just as any other. But consider this:
The book Fundamentals of New Testament Greek had this to say of the use of ego eimi in John 8.58:
Though it may seem this was a personal view of mine, its actually not at all. Can't even call it a personal revelation, some of the deeper things it implies maybe but beyond that definitely not. They were teaching what I said in the 1st century church. Paul even told the people in one of the writings, he referenced Yah from a Psalm I believe and directly related it to the Messiah.
He also took the people to Moses when he was revealing himself to them, always started at Moses. And that's where a lot of the follower started with people. I'm assuming that the reason it was lost so quickly is because of the gatherings growth required them to go over base stuff over and over again and no one matured at a rapid enough pace to make sure even the deeper things were maintained and passed on.