You’ve read it again and again. Finnis and Grisez asserted it. Joseph Seifert said the same thing in his critique. So did the forty-five theologians. It’s implicit in the cardinals’ dubia.
What am I getting at? Namely, that there are statements in Amoris Laetitia which, although they admit of a true interpretation, more easily suggest a false one, and are likely to be used to subvert the teachings of the Church. Thus, these people say, the pope as the guardian of the faith should clarify, and rule out explicitly those false interpretations.