You get a lot wrong from not knowing much about Protestant thought.
“The only reason the book of Hebrews made it into the canon was the mistaken and falsely traditional belief that it was written by Apostle Paul!”
Actually, it was known all along that Paul may not have written it. Many church fathers rejected Paul’s authorship, and Jerome was one. Luther thought it was Apollo, and it was one of several books he thought might not belong in the canon. Calvin rejected Pauline authorship. Others suspect Barnabas.
A dissenting view can be found here:
http://www.studylight.org/com/jfb/view.cgi?book=heb&chapter=000
It was not accepted because Paul wrote it.
“Most Christians to this date do not know and have never been told that Gospels were written anonymously and that it was the Catholic Church, whose authority many Christians reject, that assigned the authorship to them at the beginning of the 3rd century.”
Wrong again.Protestants know full well they are anonymous, and discuss possible authors in commentaries. Many of us have study bibles, with introductions to each book - and those almost always have a few sentences about authorship. The Sunday School curriculum put out via the SBC (but not used by all Baptists, since we are all independent) covers 1-2 books each quarter, and always includes a discussion on who wrote it.
“In fact, even the Protestants in general firmly believe, and Protestant communities continue to teach, that those were the actual authors, even though that belief has now been shown to be groundless, or at least seriously doubtful for quite some time.”
Actually, there are good arguments in their favor, as well as some against. Get a good commentary and read at your leisure.
I’m looking at the intro to Hebrews from the NIV, its says:
“Although the author of Hebrews is unknown, this book was probably written in the late A.D. 60’s...”. It did not stop me from accepting it as part of the Word of God. It’s in there because the Lord WANTED it in there.
Why don't you tell us why it was accepted? The Church accepted it on belief that it was Pauline in origin. The criteria for anything to be accepted as "inspired" was that it had to be identifiably apostolic in authorship. There were plenty of anonymous or known forgeries which were rejected.
The text of the canonization of the Christian Bible based on the III African Council in Carthage in 397 AD states somewhat strangely "thirteen Epistles of the Apostle Paul, one epistle of the same [writer] to the Hebrews."
Wrong again.Protestants know full well they are anonymous, and discuss possible authors in commentaries
Well, if they know they are anonymous, then they cannot quote them as being Mark's, Matthews', John's, or Luke's can they? It's deceiving. You may have good arguments for or against, but as long we don't know, it is a lie to present them as if we know the authors. And Christians shouldn't peddle a lie.