The mainstream or middle of Christianity certainly has been in dramatic decline over the last few decades where I live. As I highlighted in a recent thread, in New Zealand our 2018 census recorded a decline in the number of Christians from 48 to 37% in just 5 years. OTOH those who have no religious affiliation have increased from 42 to 49%. While this has been the trend since the 70s the decline is accelerating despite the best efforts of mainstream (Catholic, Anglican, Presbyterian and Methodist) Churches.
It would be interesting if the polls included increases in these fundamentalist groups ranks at the same time you see the middle collapsing and atheism increasing. These groups that are big into making converts tend to swoop in to prey upon the vulnerable. And as the mainstream churches flounder and fail, those affected by that are targeted by these groups, who show them how they were not the true church to begin with, and if they join them, then they'll get to heaven.
But the real thing they are offering that appeals to the vulnerable, is the sense of belonging to a family. The cultic nature of these, creates that sense of "family" for those disenfranchised by their own religious families falling apart as others drifted away. The belief structures are created tightly, particularly authoritatively presented, which members bind themselves to each underneath.
As a personal aside to support what I am saying, it has been a life's mystery to me personally about myself, how it is I ended up in my early 20s in one of these groups I am describing above, which resemble groups like the JWs in their own particular ways, born at that same period of time in American history. I am a rational person, and grew up raised by a father who was solidly Modernistic in thought, spiritual but not religious. A mother who was culturally Christian, Episcopalian background, who may have gone to church a total of 8 times while I was a kid, on holidays or other occasions. They were very open minded and accepting of differences in others. It was not a religious household with religious training for us growing up.
How is it I would end up in one of these fundamentalist cults? It didn't last for too long, maybe 5 years? After wrestling with this question, since my views today are quite a bit more beyond what I used to believe, or at least tried to believe, I think I have the reason for it. A family. While my family was relatively financially capable, as well as good intelligence and education, and unconditional love from both of my parents, I had a sibling who developed emotional and psychological problems while I was growing up. It hit at such a time as it disrupted the normal developing relationships between a child and his parents. It disrupted that. It disrupted many facets of my life during that time, in school, with friends, with my own happiness in life.
Then I had a spontaneous Awakening experience when I was 18, as the result going through a deep existential crisis for myself at that point in life. It was facing that existential Void, and entering to and through it that opened up Reality to me. For the moment, of course. Now I could see Life, but I was still that broken kid who had a lot to deal with coming out of that. Add to this, that vision of Light to reach to as Home. And it truly is that for me, as my past 4 decades since that has been to come Home to that.
But in that early search to come Home, to find God as I had touched and tasted That. I was encouraged to talk to Christian minsters, and none of them had anything that remotely talked to that experience. At least not for me at that time. And it was when I encountered one of these "We have the right answers, and they're all wrong" groups, that something resonated for me, strangely enough.
What it really gave me was a family. It gave me structure. It gave me a sense membership. That was the core emotional pull of it, aside from the promises they gave me that I could know God, as I had experienced it before. What I discovered though, even in those very first few months while I was happily taking it all in as much as I could hold, is that that "unity" we had, which they proudly quoted from scripture, was based upon common beliefs. It's like we were the people of the red flag, versus those who rally around the blue flag. It was based upon agreeing with each other theologically. That's not really love, I could recognize, but I did not want to acknowledge because I was getting something out of it emotionally for myself.
So that rather long, and fist time I've ever shared that before post, is to understand sympathetically what it is for people who are looking for family, and how these groups like this tend to target and swoop up the vulnerable, are picking up those like me who fell through the cracks in a family life. The same thing would apply to their church family, which is what traditionalism offers people. When the traditional church fails, the home is disrupted and people experience real genuine loss, as I did in my life growing up.
Did I gain some good from it? Sure, and I don't wish to throw out the baby with the bathwater. But that baby in the bathwater, was always me to begin with.