Makes me think of … Asperger’s.
Not capable of functioning independently or surviving for any long period unassisted but having a brain and cognition setup that allowed for amazing feats of mental wizardry. If you could have that ability and function normally in society you could do some astounding things.
A great story about a mega-savant who can function is "Understand" by Ted Chiang, if you're interested
I like that Frank Herbert imagined that it would be possible and went with it before we had any real proof that it could be, and then he turned out to be right.