These paragraphs reference Pope Francis’ 2017 document clarifying the formulation and translation process for liturgical books. You can read it here. To get the full context, you’ll need to refer to your copy of canon law too. Basically, these paragraphs make an adjustment from the years since Liturgiam Authenticam. The first of them conduct a Ressourcement to the mid-1960s, getting us back to the Second Vatican Council and its intent. Even a few months after the Constitution on liturgy, Pope Paul VI was looking ahead to the need for translation into the vernacular, rather exploding the myth that Vatican II intended a continuation of Latin as it had been before.
5. “(A)ccording to what is stated in the Constitution Sacrosanctum Concilium, in particular in articles 36 §§ 3-4, 40 and 63 and in the Apostolic Letter Motu Proprio Sacram Liturgiam, n. IX”, [Magnum Principium: AAS 109 (2017) 969] the Motu Proprio Magnum Principium has modified the canonical norms in such a way that “the competency of the Apostolic See surrounding the translation of liturgical books and the more radical adaptations established and approved by Episcopal Conferences be made clearer, among which can also be numbered eventual new texts to be inserted into these books”. [Ibid. 969] Consequently, “the right and duty of Episcopal Conferences” is also clarified, facilitating fraternal “collaboration … between the Apostolic See and Episcopal Conferences” [Ibid. 968-969] regarding the publication of liturgical books in current languages.
The relationship between conferences of bishops and Rome is to be a “collaboration,” or perhaps in a term Pope Francis uses often, an accompaniment. Not quite the role of bishops as “middle managers,” as some critics of the 1978-2013 era have described it.
2017 makes the adjustment:
6. As a consequence of the Motu Proprio, a renewed interpretation of the applicable norms issued so far about adaptations and translations for the liturgy is necessary. It should be borne in mind, however, that “the criteria indicated were and remain at the level of general guidelines and, as far as possible, must be followed by Liturgical Commissions as the most suitable instruments”.[Ibid. 968]
I would assume that ICEL and the parallels in other language groups are the bodies referenced here. #6 seems to indicate that the current guidelines for translation remain in place “as far as possible.” Who decides the possibilities? Probably that “collaboration” between bishop groups and the CDWDS.
As we reach the end of this introductory section, we look ahead to the content of the document:
7. The present decree contains guidelines and prescriptions concerning the competencies of both the Episcopal Conferences and the Congregation for Divine Worship and the Discipline of the Sacraments. The acts of recognitio and confirmatio, described in numbers 43 and 45, are necessary to give full effect to the decisions of the Episcopal Conferences and manifest the communion that binds the Roman Pontiff with the Bishops. [Cf. Lumen Gentium 23; canon law 333 § 2]
Notice that the greater good mentioned here is a unity among bishops, including the Bishop of Rome and his dicastery for worship. I wouldn’t read too much into that; unity is a quality the Bishop of Rome has always had foremost or nearly so in his ministry to the worldwide Church. This value supercedes much–and why wouldn’t it? It is the first quality of the Church mentioned in the Nicene Creed.
The link of the English translation is here.