You're changing your story. First you said the apostasy was complete by the year 100 which is why there is absolutely zero evidence of your 'true christians', even as a separate group, in the ante-nicene fathers. Now you're back to saying that the true christians existed side by side with the catholics from the year 100 on. So lets see the historical evidence for the true christians.
Was Irenaeus a Catholic? If so, he lists out all the known heresies of his time. Which of them do your true biblical Christians fall into? Or will you now claim again that they had completely disappeared to the point where an apostate Irenaeus didn't even bother mentioning them?
No, I am not changing my story. We have a misunderstanding between us.
When I said that the Ante-Nicene Fathers is the history of apostasy and that the apostasy began even before the New Testament was finished, in your mind (not mine) you believe that the Ante-Nicene Fathers is one and the same with New Testament Christianity and so you see a logical fallacy in what I said.
However, in my mind New Testament Christianity and the Ante-Nicene Father's are not comprehensive of each other. I see the Ante-Nicene Fathers as a separate branching out and not inclusive of New Testament Christianity but merely one aspect of it - apostate aspect.
Also, I see the Ante-Nicene Father's a growing apostasy that comes to full bloom in the time of Constantine. Hence, the roots of the Ante-Nicene Father's or the apostolic fathers is fairly orthodox with some seeds of apostate doctrine which gradually grow to full bloom by the time of Constantine.