For example, today a child from a religious community might encounter atheism at 12 or 13 whereas previously they would encounter it when they went off to college. Maybe that child happens to be suffering from depression and their faith would have provided them with the hope that they needed to persevere, but having discovered atheism at such a tender age, they are left hopeless and desolate. Not mature enough to deal with their problems on their own and with no reason to believe that things will get any better.
I am not saying that the rise of atheism is a factor. It is just one example I came up with, on the spot, to explain how the change of culture due to the Internet might be the actual cause powering this trend, rather than the usage of the social media itself.