Precisely.
The attitude of debunking the doctrine of the Church on Mary as Mediatrix of all graces, or any other doctrine, is symptomatic of those who place their feelings, views, desires and prejudices above Christ and His Church. It is most unscriptural:
The Church is “the pillar and bulwark of the truth” (1 Tim 3:16). St. Paul says also, “through the Church the manifold wisdom of God might now be made known to the principalities and powers in the heavenly places.” (Eph 3:10). The Church teaches even the angels! This is with the authority of Christ!
St. Paul has counseled you as to whom to avoid: “Preach the word. Be urgent in season, out of season; reprove, entreat, rebuke with all patience and teaching. For there will come a time when far from being content with sound teaching, people are avid for the latest novelty and collect themselves a whole series of teachers according to their own tastes.” (2 Tim 4:3).
“That we should no longer be children, tossed to and fro and carried about by every wind of doctrine, by the trickery of men, in the cunning craftiness by which they lie in wait to deceive.” (Eph 4:14).
St John counsels you: “We belong to God, and anyone who knows God listens to us, while anyone who does not belong to God refuses to hear us. This is how we know the spirit of truth and the spirit of deceit.” (1 Jn 4:6 ).
To overcome the prejudice, a humble obedience to Christ through His Church is the answer. Vatican II in Lumen Gentium, 62, (Dogmatic Constitution on the Church) taught that Mary is the Mediatrix of All Graces by the footnote which gave the teaching of Leo XIII, St Pius X, and Pius XII, all of whom so taught. The Council would (and could) not have so done if this was merely the expression of personal opinions by these Popes. The Council teaches that she was eternally united with Jesus in the decree for the Incarnation, and thus from eternity before time began and through all eternity (59). There are twelve Papal Texts speaking of Mary as the Mediatrix of All Graces. [See Fr William G Most,*Our Father’s Plan