@Agatha James -Your comment is true. I helped a priest, an Augustinian (now deceased unfortunatly), write a book about the disaster of Vatican II. Mostly it dealt with the USA Church. It's interesting to note that the Catholic Church in the USA never really "took off" as a religion in the USA in substantial numbers until the Irish immigrated. Between 1810-1880 the Catholic population in the USA grew by 225%. During that time, 85% of religious Orders of nuns that exist today were founded between those years, the earliest was the Sisters of Charity by St. Elizabeth Ann Bailey Seton. Her Order split into 7 branches over the next 40 years, so that by 1861, there was a branch in Baltimore, NYC, Cincinnati, Greenburg, Pa., and three others. Combined, they were in the 4,000's before Vatican II, but sadly today all 7 branches only have about combined 950 members. The biggest wave of Catholic immigrants was between 1840-1925, during which time 90% of Catholic colleges, universities, seminaries, novitiates and parishes were built. Catholic rose from less that 2% in 1820, to about 22% by 1940 (where it has remained since), though the Protestant percentage of the USA has declined from 95% in 1820, to 44% as of the 2020 census. It took almost 100 years, 1840-1940 to build most of what was the Catholic Church in the USA, and by 1960, there were only 300 parishes in the whole country without resident priests. There were about 25,000 Catholic parishes in 1960, and 6 million children were in parochial schools, 95% staffed by nuns. Today, there are about 18,000 Catholic parishes, with less than 2 million children in Catholic parish schools....99% staffed by laypeople. ( nuns decline since 1965).
So what you said is 100% true, it took close to 125 years to build up the Catholic Church in the USA into the flourishing instutution so many knew....built largely by immigrant peoples. But it only took Vatican II and it's reforms to trigger a massive collapse starting immediatly in 1965 till today, accelerated since 2013.
To me, it's proof of the work of someone other than God. Take a guess who

Yes, pennies saved mostly from very menial jobs. There was an unfortunate Protestant ethos in the USA until as late as the 1960's that said that Catholics and Jews were not to be hired for good, well paying jobs. Of course, people like Asians and Blacks were out of the picture entirely. But Catholic were barred from most jobs. It was almost impossible for Catholics to get into Ivy League schools, all the way up until the 1940's there was a highly orchestrated, bigoted wall of contempt against them. Joe Kennedy (JFK's father) spoke many times of the bad feelings and predjudice he felt as a student at an Ivy League school....he only got in because his family was wealthy. JFK himself suffered alot in the 1960 campaign from anti-Catholic prejudice.
As late even as the 1970's in movies and TV, no one was portrayed as being Catholic, or Jewish. It was always the same. WASPS. There was only 1 groundbreaking TV series in the early 1950's that featured a Jewish family, and that was a steriotype Jewish family, "The Goldbergs". When a TV series showed priests, or more often, nuns, it was considered groundbreaking. Times changed slowly. And today, sometimes in a very negative direction. Now there is at least 1 TV show, where the lead couple is in a homosexual relationship. UGH!