Maybe it's the illusion of "it would solve all our problems and give us unimaginable riches" that clouds the mind?
Like when Evolution thought it a good idea to create intelligence and humans in order to maximize reproduction of genes, and tried to sandbox them by making reproduction so pleasurable and carbohydrates so delicious they would never be able to not reproduce or stop eating. But Evolution could never have predicted what these creatures would then actually do, which is invent birth control and sucralose.
Of course it's impossible to engineer a sandbox for something much much smarter and faster than you. It will also not have only one plan prepared for escape, but fifty in parallel.