I cannot agree when there is abundant evidence to the contrary. The church population was moving forward and growing and the faith was much stronger prior to the changes 35+ years ago. Once the changes were introduced, thats when people started losing the faith and leaving in droves - and continue leaving to this day.
The magisterium is facing an unpresidented problem with the shrinking catholic population throughout the whole world that has been evident since the changes and I think they are hoping, with good reason, that returning to the Church's traditional practices will revive the Church population.
The worldwide Catholic population in 1966 was approximately 600 million; it is now over 1 billion. In the United States, the Catholic population was 46 million; it is now 62 million.
Neither of those statistics reflect a shrinking population.