I've met smart and stupid of every type. The same operating system can be run on many computers. N-types are sometimes perceived as smarter or dumber (often naive or weird) because population wise, they're approximately 20% (if not, they're a definite minority) and their perspectives often differ greatly from S-types. Some Americans think that Brits are smarter because of their accents while some others think that they're dumb for the same reason.

a.k.a. I/O