From the article above:
"The really revolutionary element of Divini Cultus, however, is that female singers of the liturgical texts were promoted by Pope Pius XI himself. As we have seen with his blessing of Justine Ward’s work, he had already approved girl choristers, even though they had been banned by his predecessor.
Americanist Card. Gibbons was a friend of Roosevelt and an opposer of St. Pius X Whereas Pius X ordered that liturgical chant should be taught to seminarians and clerics and restricted to their use, Pius XI extended this instruction to the whole Catholic population, starting in the schools. He told heads of religious communities of women as well as men to “devote particular attention to the achievement of this purpose in the various educational institutions committed to their care.” (7)
This not only means that females were also allowed to perform a liturgical function, but that choirs should be formed for their instruction in the Chant. It was a concession to the recalcitrant American Bishops. Predictably, it led to a divisive situation with Bishops everywhere taking the part of Pius XI against Pius X and leading the faithful to do likewise."
At this point, supporters of congregational singing need to ask themselves an honest question:
If women can suddenly become members of the choir (by episcopal revolt against Pope St. Pius X), thereby usurping a liturgical function, then per the Novus Ordo, what logical objection can there be to altar girls (likewise performing a liturgical function)?
Perhaps now you can see the problem with congregational singing (and the Dialogue Mass, in which women also make the spoken or sung responses, usurping a liturgical roll, and much closer to the altar than from the choir loft!)?