Typically, this is a question that you'd ask at a Alabama bar-b-q and to be thrown out to several individuals who claim some rural-intellectual status. Some will admit they attended some state university for six months before they discovered the instructor was actually a third-cousin of Einstein (so they claim). Some might even say speak up that they know sixty different math equations that relate to some electrical charge but then admit they don't know much about some Chaucer-guy from English literature or how the Sun radiates the Earth. And a handful through farming will claim enough common sense to make up for four Einstein-guys and their limitations.
There is some basic belief by brilliant people and journalists that we've surged ahead over the past fifty years and have lots of smart people around today.
Generally, ever since the mid 1980s....I've gone with the philosophy that being able to assemble information, determine values from the information, prioritize, and come to a basic summary which explains the best choice.....is the key point where you can grin and admit you are more smart than stupid.
The rest of this book-smart stuff? Worthless.
I've sat through sixty odd university-related classes via University of Maryland, Louisiana Tech, two community colleges, and the Air Force. I came to realize after reading a fairly deep summary of Greek tutors from over two thousand years ago....that education alone doesn't really do much. You need to have some ability take that information and make use of it or rationalize the big picture.
In this way, my answer is that most people probably are more stupid today....than what existed decades ago. Oh, they may have some certificate and claim to have finished such-and-such university....but beyond that....there's no comprehension.
The brighter crowd? The engineer brings in the formulas and relates them to his work. The scientist with an analytical view will be able to gauge what he sees and bring some solution to a problem. The analyst with some respect for questions will ask enough until there's nothing left in front of him except an answer.
We live in a stimulating age....where kids are hauled off from high school to a university....pay down $10,000 to $30,000 a year and get some status in life of being smarter. So far, no one much goes to challenge that behavior and we've developed this to a national stage....where kids graduate from such-and-such school....must be offered $80,000 a year for a master's degree but their measurement in wit or brightness would equal some Chinese seventh-grader. It's bad enough now that we have headhunters, who only specialize in people in this position....helping to find idiots in companies, who will hire new fresh idiots out of graduate school.
The eventuality? We probably will eventually produce enough stupid people to tell us that we need more smart people, but can't really identify the ways from which you'd produce such people. That's when you know we've gotten pretty screwed up.