That may indeed represent some of the underlying causes, and may explain why less developed countries are not yet seeing as much of a decline.
But one of the authors of this research paper, Richard Wiener (who is my brother), sees this as more of a networking effect irrespective of specific causes. Just as a language may decline and fade away due to its diminished utility, irrespective of the quality of that language, Richard believes that the same mathematical model can be fitted to the census data for religions in various countries.
I am sure there are many contributing factors. No doubt there is a “perception” of diminished utility by many. I am currently chairman of a search committee for a small Southern church. We recently interviewed a ministor who is exceptionally effective at personal evangelism but did not call him. He made some very interesting points.
The first was that he has found young unchurched people hungrier than ever to hear the gospel message. They know things are not right in our culture and they are looking for answers. If done properly, they are very receptive and responsive.
Secondly, he indicated that traditional methods of evangelizing is ineffective to younger generations because most do not know how to communicate with them. Essentially, they offend them and make them defensive before they ever get the chance to share their faith with them. Often times we Christians project the image that we have all the answers; we just seem a little too sure of ourselves. I see that very clearly since I get put out with the garbage some of them spew myself. I have been steadfast in my faith, but I have had much of my life cave in around me. I KNOW that I don’t have all the answers and I perceive that God has worked in many mysterious, and good, ways in my life.
It is wrong to sell Christian faith like a piece of candy off the shelf because that is a lie, and intelligent people realize that. Yet, at the some time, my faith has provided me with an inner strength and inexplicable guidance on occasions in my life. Sometimes it has led to blessings. A number of times it has led me to avoid decisions that would have caused me great trouble . . . most of which were counter to I normally would have done on my own accord. The “utility” of true Christianity will never diminish, though certainly, the numbers of those who find it may dwindle. The REAL problem is that Christians need to take a very close look at what they are “selling” and how they are selling it. IMHO, they are doing a very poor job of communicating the essense of what being Christian really is . . . mainly because they don’t really know themselves.