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In order to support their opinions, these people either refer to quotes from Saints and popes from fifty years ago or more that seem to contradict current Church teaching

The problem isn't that they "seem" to contradict, they do.

This excerpt from Mortalium Animos seems particularly apropos to this thread:

"...For which reason, since charity is based on a complete and sincere faith, the disciples of Christ must be united principally by the bond of one faith. Who then can conceive a Christian Federation, the members of which retain each his own opinions and private judgment, even in matters which concern the object of faith, even though they be repugnant to the opinions of the rest? And in what manner, We ask, can men who follow contrary opinions, belong to one and the same Federation of the faithful? For example, those who affirm, and those who deny that sacred Tradition is a true fount of divine Revelation; those who hold that an ecclesiastical hierarchy, made up of bishops, priests and ministers, has been divinely constituted, and those who assert that it has been brought in little by little in accordance with the conditions of the time; those who adore Christ really present in the Most Holy Eucharist through that marvelous conversion of the bread and wine, which is called transubstantiation, and those who affirm that Christ is present only by faith or by the signification and virtue of the Sacrament; those who in the Eucharist recognize the nature both of a sacrament and of a sacrifice, and those who say that it is nothing more than the memorial or commemoration of the Lord's Supper; those who believe it to be good and useful to invoke by prayer the Saints reigning with Christ, especially Mary the Mother of God, and to venerate their images, and those who urge that such a veneration is not to be made use of, for it is contrary to the honor due to Jesus Christ, "the one mediator of God and men."[19] How so great a variety of opinions can make the way clear to effect the unity of the Church We know not; that unity can only arise from one teaching authority, one law of belief and one faith of Christians. But We do know that from this it is an easy step to the neglect of religion or indifferentism and to modernism, as they call it..."

http://www.vatican.va/holy_father/pius_xi/encyclicals/documents/hf_p-xi_enc_19280106_mortalium-animos_en.html