I say this for 6 reasons.
1. Correlation does not equal causation. I read that some irreligion trends were occurring even before the New Atheism appeared on the scene. So the effects of the New Atheism movement may have been minimal. In addition, read this article American faith: A work in progress which is skeptical that the New Atheism had much of an impact:
2. New Atheism appears to be gobbled up by feminism/SJWism ("social justice warriorism")/political correctness within atheism as this story indicates: The Collapse of New Atheism.
Feminism has an element of trendiness too as this roller coaster Google trends graph helps show, but feminism did help to largely kill off New Atheism. In addition, political pendulums do have a tendency to swing back and forth in the United States and there does appear to be a growing backlash against "political correctness" and right-wing candidates are gaining traction in many elections around the world.
On the other hand, different brands of atheism are often reactionary to various types of theism/politics so perhaps SJW has some legs for awhile. But given the roller coaster nature of feminism in society and the fickleness of the fairer sex, I have my doubts about feminism/SJW type atheism lasting. I think it is largely a fad.
3. Economic instability increases religiosity and the global/U.S. economy seems fragile right now.
4. Furthermore, there are some powerful global trends in terms of a global resurgence of religion and in an age of globalization, this could certainly have an effect on the United States,
5. The New Atheism caused a surge of anti-atheism defenses of Christianity being published in print and on the internet. Now it seems as if Answers In Genesis may see a big surge in publicity due to their Ark Encounter exhibit which is an impressive and fairly close replication of Noah's Ark (It does have a restaurant in it which I doubt Noah had). And I am not sure if the Amish who helped built the Ark Encounter used the mysterious wood of gopher wood!
I liken the New Atheism inspired Christian anti-atheism works to be similar to the United States battle with Japan in WWII. They intellectually conquered a lot of islands on the way to "Japan"/atheism, but the "mainland" of ideological underpinnings of modern day atheism/agnosticism is Darwinism.
(Perhaps, it might be better said that Christians reconquered many islands on the way to "Japan/atheism" as the Christian vs. atheism battle is a battle that has been going on the West for about 400 years. Admittedly, new arguments do come forth. Although the New Atheism brand of atheism was largely a marketing tactic as much of it was not new.)
Darwinism is intellectually bankrupt as these 15 questions for evolutionists help show. Creationist have a lot of excellent content at this point. If they just amped up its distribution into the marketplace of ideas, I think this would have an effect.
Johns Hopkins University Press reported in 2014: "Over the past forty years, creationism has spread swiftly among European Catholics, Protestants, Jews, Hindus, and Muslims, even as anti-creationists sought to smother its flames."
On February 24, 2015, the Science Nordic website declared:
Creationism, the belief that a god -- not evolution -- shaped life on Earth, is ... spreading in the very stronghold of evolution, Europe. That’s the conclusion of five years of research that’s been put into new book on creationism. The book details how creationism is on the march throughout most of Europe.
"Creationism is most dominant in Eastern Europe and Turkey, but even some schools in the Netherlands are teaching creationism," says one of the book’s authors Hans Henrik Hjermitslev, University College South Denmark. "Politicians in some German federal states are advocating that schools use creationist books alongside those about evolutionary theory in their lessons. This kind of struggle is going on on a small scale in many places."...
"Over the last ten years we’ve seen the emergence of big-city creationism. London is a good example," says Kjærgaar.
Here, noticeably more young people have been signed up to various local and religious groups.
"And this doesn't just apply to young Muslims as many people might think. Christian groups are also recruiting young people...
Creationism has particularly been on the rise in step with the internet, which according to Peter Kjærgaard has made it much easier for people to become activists..
Darwinism has public schools supporting it. On the other hand, homeschooling and the use of vouchers for private religious schools is increasing and many people are becoming dissatisfied with the quality of public schools. Given aging populations in the West and accompanying tight government budgets, privatization of public schools (which is more economical) could gain further traction though increased use of homeschooling vouchers, etc. Necessity is often the mother of invention so societies may become less reliant on the public school model of education.
6. The percentage of Americans who say they believe in God has recently seen an uptick according to a recent report by the Gallup organization, but perhaps this is a sampling error as Gallup says "the margin of sampling error is ±4 percentage points at the 95% confidence level."