Synanon was just one insane phase of a weird American self-help/productivity/management religion which seems to have started with José Silva and his UltraMind ESP System, almost immediately reached its final form through William Penn Partick and Leadership Dynamics/Holiday Magic, then after Synanon becoming basically the entire 70s with est etc., next during the 80s the self-help book boom and the rise of pop management theory then lasting throughout the 90s, and the TED talk culture now.

If Synanon hadn't tanked, they'd be controlling half of the country by now. Jordan Peterson looks like a Synanon revival from what I hear about him.