No, Catholics haven’t “lost the nation.” Catholics never had it in the first place.
Evangelicals, mainline protestants, Catholics and others have been the predominant religious groups in the USA, and Americans have always been very religious people.
BUT Americans, like Europeans before them, are in the process of shifting their moral beliefs from religion to a fake idea of science and to government. And there the majority of Catholics are no different than anyone else in the culture. This is why the behavioral metrics are almost identical between Catholics and the general population. They are statistically indistinguishable the great majority of the time.
Of course, when their governments eventually tank, as all governments do, they’re going to be between a rock and a hard place, but that’s not the issue for them now. They’re too busy with what they’re doing. Just like the Roman Empire was before them. Some things never change.