Supposedly Pope Paul “asked” the bishops to find a way to make Jubilate Deo work, or something to that effect. I suppose you can call that hortatory, but if my mother “asked” me to do something, I sure considered it a command.
And therein lies the problem.
If the Church wanted to turn things around, they could easily make certain music mandatory. For nigh on 50 years, and a number of re-writes of the GIRM, they have clearly chosen not to. Not that there are not some who want, even dream, of that happening; but they refuse to see what is right in front of them.
The music will be used, even as it is currently being used, in some parishes. It is a bit akin to the issue of the EF being celebrated; it is most definitively in a minority. There are some few people, if they could be “pope for a day”, would implement that as the first rule made.
But they are not; Francis is, and as the last 4 Popes and the current one did not and do not appear intent on making certain music mandatory, so then it will not be mandatory.
Many people have the impression of a top-down structure in the Church; one that Rome says “jump” and parishes and diocese ask “how high” on the way up. I am not sure if that has ever been the case. And while Rome does make rules, there is also the reality in the Church for the better part of the last 2,000 years, that some things have come from the bottom up. Music appears, at this time, to be one of those.
Looking back to when the EF was made available, there were those, including some in these threads, who in so many words predicted that there was coming a tidal flood of immense proportions, such that the OF might even be eventually replaced.
That hasn’t happened, and a very wise individual said that he didn’t think that it would happen - Benedict 16 in his accompanying letter.
None of that is to pass on the worthiness of the Church’s desire that certain music be given pride of place. I am not challenging that; simply pointing out the Rome is not ignorant of what goes on in the US, and the fact that they do not object to it.