Today's youth in the US are spoiled; so many having never worked a day in their lives, supported by their parents (and or loans/taxpayer grants) from birth until the end of graduate school.  When you've never had to worry about providing your own food, shelter or clothing, then your "spiritual" priorities are activities like art, theater, dance, phone apps, music, sex, Starbucks, travel, parties, etc....  Which is all fine until the gravy train stops or worse, when you realize that you've spent your life solely on your own desires.  Then what?  Therapy, anti-depressants, recreational drugs, and other crutches; these are the new substitute for religion.  

Where is true religion prospering?  The Third World or anywhere where people struggle to support themselves and their families.  

It's so easy to be "spiritual," i.e., have no need for God, when all of your needs have been tended to by others.  There is no perceived need for houses of worship.