The phrase "pure stupidity" means a complete lack of intelligence or common sense. It describes someone who makes very foolish or illogical decisions. Full definition
That said, the film is very much your standard sex comedy filled with generic characters that are never fully developed, cheap gross - out gags and several moments of pure stupidity. (weliveentertainment.com)
Sadly, there will probably be another short sale that will never make it to the closing table because of pure stupidity. (massrealestatenews.com)
This is merely the logical outcome of our death penalty driving bloodlust in my view and there's no good reason it ought not be pursued (we've spent trillions of dollars on this after all, and surely we didn't spend all that money on pure stupidity and evil did we?). (slaw.ca)