I was the retreat chairman for the Men’s retreat through the 80’s and 90’s
When I made my first retreat back in 1978, we had 150 men on retreat.
This is after Vatican II, which had nothing to do with the decline.
Instead, the decline coincided with the decline in people attending Mass, especially as the sex abuse scandal rocked the Church. One case was by a member of the retreat team where the retreats were held.
Also, the cost for retreats increased greatly. It’s suppose to be a free will offering, but they did tell us how much the retreat costs and to leave more for those who don’t have enough to cover the cost. They never turn anyone away, but there are many who will not make a retreat for which they can’t pay.
In all, blaming Vatican II for all the ills in the Church merely shows an ignorance to what took place in the Church before Vatican II, but back then, it was kept out of public view. There’s more transparency in the Church today, but it’s not even close to being good enough.
Jim