In the 1950s I was born and spent the first 7 years in the Monterey Peninsula. My overseer father and pioneer mother had previously helped form the congregation. They brought me home from the hospital to live in the apartment above the Kingdom Hall.
Our congregation had a doctor, a female college professor, a building contractor who handcrafted violins and incredible Swedish furniture, a radio actress, a retired actual cowboy, a chiropractor, and an entrepreneur to name the ones I remember. I was the only child in the hall until I was six! Most of the ones I mentioned before were childless or their children were already grown. All were hard working or retired and lived comfortably or better.
It was a different religion then, much worse for children with the weekly talks stressing corporal punishment and vivifying Dr Spock. Yet, it was better for the adults in that they could freely speculate and even debate certain aspects of "The Truth". And they DID in my presence.
Most of the people were intelligent or gifted or both. They simply were disgusted with the clergy of Christendom and became JWs because they were "not a religion" and neutral to politics.
Of course the 1960s brought huge changes to society in general but the borg exploded with growth -especially in the mid 60's to mid1970s. Many joined who were poor or uneducated looking for a way out of their miserable life or disgusted with the Vietnam War. A message of paradise coming in just a few years or even Months was too good to resist. Gradually, the free thinkers were silenced or died. The converts tended to "serve for the reward" and the rest is more history.
i