This general audience by Pope Francis is worth reading. It seems to be another implicit commentary on his critics.
“Dear brothers and sisters, this first exposition of the Apostle to the Galatians presents the radical newness of the Christian life: all those who have faith in Jesus Christ are called to live in the Holy Spirit, who liberates from the Law and, at the same time, brings it to fulfillment according to the commandment of love. This is very important. The Law leads us to Jesus. But one of you might say to me: “But, Father, just one thing: does this mean that if I pray the Creed, I do not need to observe the commandments?” No, the commandments are valid in the sense that they are “pedagogues” [teachers] that lead you toward the encounter with Christ. But if you set aside the encounter with Jesus and want to go back to giving greater importance to the commandments, this was the problem of these fundamentalist missionaries who had infiltrated the Galatians to confuse them.”
Those who infiltrate the Church and the Gospel are not the Popes and Bishops, but rather those who are rebelling against Church leaders. Pope Francis is like Saint Paul, and those who infiltrated to confuse the Galatians and lead them astray are like the critics of Pope Francis and the opponents of TC.
the reproach of Christ 
It is also good to note that, making a parallel between (i) (a) the Covenant and (b) the (Mosaic) Law; and (ii) (a) the New Covenant taught by Jesus at the First Mass (the Last Supper) to His Apostles (a Mass that was instituted without immutable specifics) and (b) the Latin Mass (the disciplinary liturgical form). Though the Latin Mass is good and holy in itself, it does not bring salvation by being attached to it, so a Catholic shall “not to be nostalgic for times gone by” – as the Pope put it in this audience. Rather, FAITH out of LOVE in Christ and His teachings is what brings us to salvation. This is a test that God is bringing to the table to see if we are too attached to a form of Mass rather than having faith in His Church. Sadly, many are failing. A Catholic shall be faithful to the Magisterium because they have the authority given by Christ Himself, His Spouse is let by the Holy Spirit. Any disciplinary change that the Magisterium brings from time to time, it is good with Jesus (Matthew 16:18-19) (Matthew 18:18). The Holy Spirit guides the Church (CCC# 85, 95-96), thus what the Magisterium teaches, is good with the Holy Spirit. Pope Francis mentions in this general audience: “For it has seemed good to the Holy Spirit and to us [the apostles] to lay upon you no greater burden…”. Notice that the Apostles didn’t say “it seems good to us”, BUT, “It has seem good –>to the Holy Spirit and us”<– (AS ONE). So the change that the Apostles was bringing to the table at that time, came from the Holy Spirit (it was not something that the Apostles just came out with it because they wanted), so it is now with the Pope and the Body of Bishops in communion with the Pope. Tradition Custodes came to place because it seem good to the Holy Spirit. Whoever rejects it, rejects the Holy Spirit.
Acts 15 is a good read for it explains how some early Christians were teaching things without the authorization of the Apostles, so they appointed some authorized men (Acts 15: 24). So it is happening today that some (sadly) bishops who are braking communion with the Pope and the body of bishops in communion with him, some priests, some, speakers, popular youtubers, etc., are teaching things that the Magisterium has not commanded.