The Internet killed Scientology.
It is possible to make a closed belief system thrive and expand in the absence of open access to facts. North Korea as rather successful in its push. China less so, though they have been eager to control the flow of communication.
Religions have long been able to sell beliefs contrary to fact by relying on empathy or force, group pressure or by pushing belief in tools designed to solve personal problems. Scientology is no different. Except Scientology came very late to the show. And it got blasted by open access to facts, freedom of expression, of criticism and exchange of ideas. It got hit by the Internet before it really got off the ground. And I think it serves well as a micro-example of the fate of closed belief systems.
Beliefs tend to fuel discussions, facts tend to defuse it.
And as Scientology finds itself being defused by the Internet, so will other, larger religions. But since the large religions are more established with a longer history, they will take longer to fade by exposure to the Net. But they will fade.
Proven methods will rule, even very workable methods that are currently suppressed by the mainstream will thrive and expand.
Openness and free exchange of ideas and facts drives all kinds of changes. It decentralizes power. It upsets establishments. It makes for a faster-paced world where old, closed belief systems are challenged and eventually die. The big religions can look at what has happened to Scientology and predict their future.
How the Internet changed the game (from NPR):