I actually haven't suggested it is.
But seems to me that if one is going to have a position, one way or the other, one ought to have a good reason.
Coming from the Lutheran POV, we actually don't have an official position on the canonical status of the Deuterocanonicals one way or the other, our Confessions are entirely silent on that issue. Luther's opinion on the Deuterocanonicals do not have official status in global Lutheranism. This is markedly different than the Reformed position which is articulated in the Reformed confessions, including the Reformed-influenced Articles of Religion used by the Anglican Communion. Reformed Protestantism, and its denominational descendants (that includes the Arminian Protestants and later Methodists and their denominational descendants) have an official position on the Deuterocanonicals as not being canonical Scripture--Lutheranism makes no such claim.
My point is simply this: The Canon is shaped by the Church, through the received confession and tradition of the Christian Church through the last two thousand years. We have a Bible because those who came before us preserved, copied, and gave us the Bible. Without this we'd have no Bible, we wouldn't have any access to Scripture, or even know what Scripture is or isn't. By denying the historic voice of the saints we end up, fundamentally, denying the Scriptures themselves and we are left without God's holy and precious word.
One cannot find the Canon in the Canon--it's not there. The Canon, as an idea, is objectively speaking, extra-biblical. If a person is honest they'll admit this, but to admit this would mean that certain ideas about the Bible have to be discarded because they do not conform to reality, neither to the contents of Scripture itself or to the historical realities that have shaped the Biblical Canon.
-CryptoLutheran