It appears that everyone is interpreting text however they want and that it is unreliable.
You are certainly. And so is Price. More careful scholars construct detailed analyses of the whole and parts which make up Mark (and the other gospels) and then compare them with other works in different genres to see how they relate. Now, if you don't ignore this post because it is inconvenient for your argument, I wonder how you would deal with the arguments presented by these scholars? They don't simply interpret the text how they want. In fact, these academic works are either largely or solely devoted to how one should interpret the gospels in terms of genre, content, purpose, etc, and they use a great many arguments to support (rather than assume) their position.
Perhaps even more importantly, while you are prefectly content to rely on online material by a non-expert like R. G. Price, have you ever actually read scholarship on gospel genre which looked at this question in great detail, and how would you adress these arguments in support of your "allegorical fiction" hypothesis?
Bryan, C. (1993).
Preface to Mark: Notes on the Gospel in Its Literary and Cultural Setting. Oxford: Oxford University Press.
Burridge, R. A. (2006). Gospels. In J. W. Rogerson & Judith M. Lieu (Eds)
The Oxford Handbook of Biblical Studies. Oxford: Oxford University Press. p. 433
Stanton, G. N. (1974).
Jesus of Nazareth in New Testament Preaching Society of New Testament Studies Monograph Series 27. Cambridge: Cambridge University Press.
Talbert, C. H. (1977).
What is a Gospel? The Genre of the Canonical Gospels. Philadelphia: Fortress Press.
Aune, D. E. (1987).
The New Testament in Its Literary Environment. Philadelphia: Westminster.
Frickenschmidt, D. (1997).
Evangelium als Biographie: Die vier Evanelien im Rahmen antiker Erzählkunst. Tübingen: Francke Verlag.
Wills, L. M. (1997)
Quest of the Historical Gospel : Mark, John and the Origins of the Gospel Genre. London: Routledge.
Incigneri, B. J. (2003).
The Gospel to the Romans: The Setting and Rhetoric of Mark's Gospel. Leiden: Brill.