They are not. Liturgy is not a matter of faith, and has never been formally defined as such.
However, many of these practices which arose after Vatican II--mass in vernacular languages, Communion in the hand and under both species to the laity, priest facing the people--were in fact those carried out by the Protestant Reformers to deny the Real Presence and the sacrifical element of the Mass in favour of a symbolic celebration of a meal. For that reason alone, these changes are contrary to Catholic faith.
This is so riddled with falsehoods as to be laughable.
Communion in the hand can, in fact, be traced back to Jesus Himself. Did the apostles stick out their tongues to share in the Bread Jesus gave them?
The Last Supper WAS a meal. The Real Presence in the tabernacle is the same Real Presence as is celebrated in the Mass.
The Tridentine Mass is a manner of celebrating the Eucharist. The Novus Ordo is as well.
The SSPX is simply not going to turn back the clock and force the reimposition of the Tridentine Mass.
Those who wish to celebrate it, should do so.
In other regards, your correspondent is quite correct. All Reformation churches removed as much Latin as fast as possible.
In a way, it is clear that the promise regarding the 'gates of Hell' applies to the Roman Catholic Church--because we have seen those gates (especially in Milwaukee) and have not yet disappeared.
This is so riddled with falsehoods as to be laughable
Communion in the hand can, in fact, be traced back to Jesus Himself. Did the apostles stick out their tongues to share in the Bread Jesus gave them?
COMMUNION IN THE HAND
"Communion in the hand" is a Protestant innovation foisted upon the Catholic world in the name of false ecumenism. The Novus Ordo practice of communion in the hand is rooted in the rejection of the Catholic doctrine on the Holy Eucharist and the denial of the Catholic priesthood.
The Church has condemned communion in the hand from the early centuries on: ST. SIXTUS I (115-125). Prohibited the faithful from even touching the Sacred Vessels: "Statutum est ut sacra vasa non ab aliis quam a sacratis Dominoque dicatis contrectentur hominibus..." [It has been decreed that the Sacred Vessels are not to be handled by others than by those consecrated and dedicated to the Lord.]
POPE ST. EUTYCHIAN (275-283). Forbad the faithful from taking the Sacred Host in their hand.
ST. BASIL THE GREAT, DOCTOR OF THE CHURCH (330-379). "The right to receive Holy Communion in the hand is permitted only in time of persecution." St. Basil considered Communion in the hand so irregular that he did not hesitate to consider it a grave fault.
COUNCIL OF SARAGOSSA (380). It was decided to punish with EXCOMMUNICATION anyone who dared to continue the practice of Holy Communion in the hand. The Synod of Toledo confirmed this decree.
POPE ST. LEO I THE GREAT (440-461). Energetically defended and required faithful obedience to the practice of administering Holy Communion on the tongue of the faithful.
SYNOD OF ROUEN (650). Condemned Communion in the hand to halt widespread abuses that occurred from this practice, and as a safeguard against sacrilege.
SIXTH ECUMENICAL COUNCIL, AT CONSTANTINOPLE (680-681). Forbad the faithful to take the Sacred Host in their hand, threatening the transgressors with excommunication.
ST. THOMAS AQUINAS (1225-1274). "Out of reverence towards this sacrament [the Holy Eucharist], nothing touches it, but what is consecrated; hence the corporal and the chalice are consecrated, and likewise the priest's hands, for touching this sacrament." (Summa Theologica, Pars III, Q. 82, Art. 3, Rep. Obj. 8)
COUNCIL OF TRENT (1545-1565). "The fact that only the priest gives Holy Communion with his consecrated hands is an Apostolic Tradition."
POPE PAUL VI (1963-1978). "This method [on the tongue] must be retained." (Apostolic Epistle "Memoriale Domini")
POPE JOHN PAUL II (1978-). "To touch the sacred species and to distribute them with their own hands is a privilege of the ordained. (Dominicae Cenae, sec. 11)
"It is not permitted that the faithful should themselves pick up the consecrated bread and the sacred chalice, still less that they should hand them from one to another." (Inaestimabile Donum, April 17, 1980, sec. 9)