Claim #1: Vatican II contradicted previous claims about other religions and salvation
There are two forms of this argument. The first one is that the council of Florence and Vatican II contradict on the issue of salvation. The council of Florence states in Cantate Domino:"The most Holy Roman Church firmly believes, professes and preaches that none of those existing outside the Catholic Church, not only pagans, but also Jews and heretics and schismatics, can have a share in life eternal; but that they will go into the eternal fire which was prepared for the devil and his angels, unless before death they are joined with Her... No one, let his almsgiving be as great as it may, no one, even if he pour out his blood for the Name of Christ, can be saved, unless he remain within the bosom and the unity of the Catholic Church."Whereas Vatican II states in Lumen Gentium:
"Those who, through no fault of their own, do not know the Gospel of Christ or his Church, but who nevertheless seek God with a sincere heart, and, moved by grace, try in their actions to do his will as they know it through the dictates of their conscience—these too may achieve eternal salvation."People have stated that these two excerpts contradict each other on the matter of salvation, but these people don't understand the idea of spiritual communion. That is, the idea that someone who isn't a member of the church due to ignorance of it or lack of accessability, among other factors, but would otherwise be a member of the church can still be saved. This was an idea held very long before Vatican II, as seen in the following quotations:
“If, however, some were saved without receiving any revelation, they were not saved without faith in a Mediator, for, though they did not believe in Him explicitly, they did, nevertheless, have implicit faith through believing in divine providence.” - Thomas Aquinas, Summa Theologica, II-II, Q. 2, A. 7, ad 3
“Those who are ignorant of the true religion, if this ignorance is invincible, are not guilty of any fault in this matter in the eyes of God.” - Quanto Conficiamur Moerore, Pope Pius IX, 1863, §7
“If a man should have no opportunity of hearing about Christ, but should follow the guidance of natural reason in seeking good and avoiding evil, we must hold that God would either reveal to him by an interior inspiration what he must believe, or would send some preacher of the faith to him.” (Grammar of Assent, St. John Henry Newman, 1870, Chapter 10)It seems pretty clear from those citations that the church generally viewed that someone can indeed be saved without being a formal member of the church, all Vatican II did was make this very widely held belief canon. The other form of this argument is that Nostra Aetate contradicted previous church teaching by saying that some parts of other religions are good. The key word here though is some, Nostra Aetate simply views that some parts of other religions are good, not that the entirety of them are good. To add to that, only 3 Vatican II documents are considered infallible teaching, Nostra Aetate is not one of them.
Claim #2: Novus Ordo is the source of many liturgical abuses
People love to cherry pick examples of various liturgical abuses (e.g the infamous clown masses) that have occured after Vatican II, which of course is a poor argument simply because it is cherry picking, but since the obvious conclusion the people arguing this are trying to lead to is that Vatican II was a bad council, I will respond by pointing out that masses prior to Vatican II were often borderline incoherent. Priests had a strong habit of speeding through masses (many were even only 15-20 minutes long as a result), as well as speaking too quietly, not to mention the fact that all masses were in a dead language. Just as one example, I found an audio clip from Kennedy's funeral. But more could be found from literary works at the time (I will also add this article going further in depth, but I rest my case).And like I said at the beginning of this article, Vatican II haters are not traditional Catholics. Catholics ever since the beginning have believed that you should obey your bishop and the pope. As St. Ignatius of Antioch said:
“It is fitting, therefore, that you should be obedient to your bishop and contradict him in nothing; for it is a fearful thing to contradict such a one… For anyone who acts apart from the bishop, the presbyters, and the deacons does not have a clean conscience.” - Chapter 5, Epistle to the Ephesians