Religion is decreasing because of a concerted push by elites to get it out of the way. A lack of adherence to a clearly defined moral code allows things like this to become normal on society. It essentially will allow the elites to redefine the value system of the masses, which will obviously be favorable to those at the top. Al Gore himself has come out saying that the population in Africa needs to be managed, and pushing homosexuality is one way to do it because homosexuals can't have kids naturally.This is why there is a concerted push to disseminate this sort of behavior among blacks. Blacks have long been looked upon as an 'undesirable race' amongst the elite.
And that's the entire goal of this rise in atheism, feminism, LGBT, etc...
You think once LGBT have all their made up rights they're going to stop? What does is it matter if you can marry when your church refuses to? That you are equal when others still hate you?
The only way to solve this 'problem' is to change people's mindset, their perceptions of what sin is.
The same thing happened with Feminism, the women's suffrage movement started out with the noble goal of making Men and Women equal under the law.(Which I agree with)
After this happened they didn't stop, instead they kept pushing for more and today you see it has degraded into articles about rape culture, sensitivity training, and the sudden attack on masculinity and promotion of femininity.
These groups no longer fight solely for rights but for change on how values and morals are perceived.