There’s nothing unnecessarily wordy about “suspension of disbelief.” It’s shorter than “turn your brain off and stop thinking critically.”
How about naivete, gullibility, cedulous, callow, unwary etc etc. the list is endless.
To be honest my distaste from the term orginates here...
http://exposingtheleft.blogspot.com/2007/09/hillarys-purple-prose.html