It was indeed, and the participants even have names for themselves: sesentayochistas, in Spanish, and something similar in French.
I have always felt that if the Church had held strong, things might have turned out differently. But it collapsed too.
And while the French and Germans had been busy nourishing clerical heretics for decades, I think a lot of the liturgical and practical changes reflected the desire of American Catholics to stand out less. The intellectual underpinning, of course, was the German Higher Biblical Criticism with its faux archaeology of the "primitive" Church, a mythical time of purity that the Protestants believed preceded Romish corruption.