jwfacts this is the Mormon study that claimed to show the impact of the Internet on growth is neutral. They don't really talk in terms of the church being undermined by online information (it's a pro-Mormon angle) but that's a major consideration, reading between the lines.
http://cumorah.com/index.php?target=view_case_studies&story_id=339&cat_id=8
Here is the blog post on the topic from a very interesting blog on Mormon growth.
http://ldschurchgrowth.blogspot.co.uk/search/label/The%20Internet%20and%20LDS%20Growth
Paul I agree with the additional factors for JW decline you mention. In particular the increasing acceptance of homosexuality is a problem for JWs. I think in the past many gay people remained JWs because they wouldn't find acceptance outside the religion anyway. Nowadays the contrast between acceptance outside the religion and stigmatisation inside the religion is pretty stark, and probably pushes most young gay people to leave.
But I disagree when you say that "information" and science and so on are responsible for the decline of religion. I disagree for two reasons. Firstly I think it misunderstands how science and faith interact in a way that former JWs are particularly prone to misunderstand this issue. But more importantly the proponents of secularisation theory are particularly at pains to point out that the process of secularisation is not the result of science disproving religion, or information exposing religion or any such thing. The roots of secularisation are much deeper and social than that. In particular it results from individualisation, capitalism, egalitarianism, social differetiation, pluralism, relativism, technological consciousness, and compartmentalisation, among other social factors outlined by Steve Bruce and other social theorists.
It's getting a bit old now but I still think the best explanation of secularisation is this book.
https://www.amazon.co.uk/God-Dead-Secularization-Steve-Bruce-ebook/dp/B000W278JW
On the other hand there is a brand new book by historian Callum Brown, who emphasises cultural and gender reasons for religious decline. In his latest book "Becomign Atheist" he draws on a number of JW examples. Which should not be surprising because JWs are particularly prone to becoming atheist.
https://www.amazon.co.uk/Becoming-Atheist-Humanism-Secular-West/dp/1474224520/