A Protestant pastor quotes a "Rabbi" (another Protestant pastor of Jewish upbringing) for the proposition that Catholics have incorporated Mary into the Trinity (now a "Quadrinity"), here. This view is based on the latter's experience while attending a mass celebrating Mary's crowning as Queen of Heaven.
No doubt, some of what he saw would have made me uncomfortable in my pew, e.g., "The priest spoke of Jesus as “Mary’s only begotten Son." The word "begotten" seems like an unnecessary qualification under the Catholic scheme.
But the thrust of his criticism seemed to be that the Biblical support for the priest's (and the Catholic Church's) views on Mary were lacking.
I am sympathetic. Unfortunately, I am plagued by the view that Biblical support for the view that everything must be supported solely from the Bible is lacking too.