Hey, a typical person should be intelligent because we human have used ourselves as a de-facto definition of intelligence anyway. That sentence probably means something like "no intellectually disabled person here". Even though we don't normally feel so because higher educations seem "typical" to us.

I think the article used a different colloquial meaning of “intelligent”, more akin to “intellectual” (the noun), as in “well educated”.

Either way, an odd statement shouldn’t normally instantly invalidate the whole article.