So, what fools Dubay, who lacks faith, and has also caused many to lose their faith, is precisely the stuff he outlines, the similarities to Our Lord's message and even life in other "religions" and even other real historical figures, so that one concludes that it's unlikely these were coincidences, and therefore one must have derived from the other. They promote this type of crap in various so-called "comparative religions" classes. I recall at even nominally Catholic universities that there were heavy implications that there was a conflation between Jesus and Mithras, for example, between whom there were numerous striking parallels.
We who have faith know full well that demons have been active throughout human history prepetrating all manner of mischief. Knowing the prophecies about the Messiah, the demons often constructed parallel events and distractions. We saw that even at Lourdes, where multiple copy-cat (diabolical) visionaries came out of the woodwork in an attempt to discredit the genuine apparition.
Do we really believe that ancient people were just so stupid that they just decided that anything they didn't understand were gods, and they just worshipped these statues for no apparent reason?
Absolutely not. We even get hints of it in the Old Testament. We have missionaries attesting to it. Demons would inhabit and animate these statues, and work wonder and other apparent miracles, and even reward their devotees with various favors, etc. These weren't just a bunch of imbeciles grunting and groaning with their clubs and just imaging that these carvings could do anything. They actually could and certainly DID do many of the things that they attributed to them. After seeing the wonders that the God of Israel had worked for the Jews after Exodus, did they really think that worshipping a golden calf would do anything for them? Well, yes ... yes they did. These idols undoubtedly would grant their wishes, and they were tired of being in the desert and wanted the old flesh pots of Egypt ... and so they rolled out a golden calf in order to elicit a response which, to the extent God permitted, would be forthcoming from a demonic entity.
So, to the extent that there were copy-cats of Our Lord out there, these were indeed not just coincidence, but the explanation is not what Dubay and others attribute to it. Instead, these "apes" of the True Messiah were created by demonic entities, attempting to throw chaff out there in order to make it difficult to see the True Religion.