From the liturgy by Joseph Ratzinger

“This expansion of papal power in the area of ​​liturgy gave the impression that the Pope, in essence, had absolute power over liturgical matters, especially if he acted by virtue of a mandate from an ecumenical council. The effect of this impression was particularly visible after the Second Vatican Council. The idea that the liturgy is a gift, an unmanipulable reality, had all vanished from the consciousness of Catholics in the West. Yet, the First Vatican Council had defined the Pope not as an absolute monarch but as the guarantor of obedience to the revealed Word. The legitimacy of his power was linked above all to the transmission of the faith. This fidelity to the deposit of faith, as well as its transmission, is particularly relevant to the liturgy. No authority can ‘manufacture’ a liturgy. The Pope himself is merely the humble servant of its harmonious development, its integrity, and the permanence of its identity.” […] The grandeur of the liturgy, it bears repeating, lies precisely in the fact that it escapes arbitrariness

Joseph Ratzinger, The Spirit of the Liturgy, p. 200-201.