I think the author is falling into a very common misconception, i.e. that there is only one kind of intelligence, and that “smart” means only one thing.
There are many different kinds of intelligence, but the one he’s talking about is rewarded by our school systems: the kind of intelligence that excels either at symbolic and mathematical exercises, or at language and writing, and certainly at sitting still, being obedient, and paying attention. The ability to memorise and regurgitate on command is also heavily rewarded by our testing systems.
These are all useful abilities, especially in a complex hierarchical civilisation with lots of bureaucracy and advanced sciences; but scholastic or scholarly intelligence is not the only kind.
Almost all of us have known some near-savants, if we’ve hung about in academia at all: people with phenomenal abilities in a narrow field, like maths or physics, but startling deficits elsewhere. Sometimes these folks are “on the spectrum” (functional autists) and sometimes they are just plain “weird”. One of the most brilliant young astrophysicists I knew in my earlier life committed suicide. Some others were perceptibly “odd” and had difficulties engaging socially with other people. And then there were those who “won the lottery” and had enough social skills to “pass for normal” while still being brilliant in their speciality.
I’ve known an absolutely marvelous classical violinist who could not figure out how to wire up the muffler on his car so it didn’t drag on the asphalt (I had to do it for him, with a coat hanger and about 5 minutes’ modest effort). I know more than one very able and thoughtful craftsman (yes, they have all been men) who could without hesitation design and build the most beautiful and functional structures — cabinetry, boats, houses — but who are dyslexic as hell and can’t spell, write, or even read fluently.
I’ve known people with remarkable emotional and social intelligence who could de-escalate a tense situation, instantly figure out what was going on in a troubled relationship, gently get information out of someone that no one else had a hope of discovering; yet many of these people had difficulty balancing their chequebooks and glazed over when confronted with numbers. My grandmother, who left school at 12 to work as a housemaid, could invent her own 3d multi-coloured knitting patterns out of thin air. I’ve known people with remarkable oral and written fluency, huge vocabularies, and enormous self-confidence — “smart” people — who nevertheless fell for the most obvious con artists and lost huge amounts of money that way.
Our author here seems to have accepted the narrow and conventional definition of intelligence as “those skills and aptitudes that are recognised and rewarded by our school systems”. And yes, it can be lonely to excel in those areas. As “the smartest kid in the class” during my school career, I can relate. Pushing the grading curve upward doesn’t make you popular. That unpopularity can contribute to delayed social development, with long-lasting effects. The fault here, I would say, lies with a harshly competitive grading system that pits students against one another.
Despite a lonely adolescence and a defensive tendency to look down on the peers who rejected and resented me in school, I also know that in adult life, we don’t have to make friends and bond only with people whose measured IQs (whatever that measures!) are within N points of our own. I have found it quite possible and actually rewarding to learn to appreciate and admire forms of intelligence different from mine, rather than thinking that other people are just generically dumb because they can’t compose a snappy blog post, solve sudoku, do the Telegraph cryptic crossword, win a chess game, or scan and grasp the gist of a legal document as fast and as well as I can.
My life partner is dyslexic. I, by complete contrast, have been reading fluently since the age of 2 and can’t see a cereal box without proofreading it :-) I have nearly eidetic memory for spelling, and a very conservative ear for English grammar. At one time I could read in four languages. I can type nearly as fast as I can speak. But… I’ve more than once seen my “dumb” partner solve a carpentry problem in the most elegant and brilliant way, a solution that I would never have thought of. And I have great respect for anyone who can solve a problem that I can’t :-)
So I think we are better off considering our various intelligences as quirks or idiosyncrasies rather than virtues, and then trying to enjoy and make the best of them, rather than valuing one kind of intelligence to the exclusion of all others. Right now we live in a time and culture where excelling at conventional scholastic skills can lead to financial and social advancement and security. In another generation or two, being able to build stuff out of scrap material or grow potatoes might be more important. You never know.
I do really enjoy solving the Telegraph cryptics. But I don’t think my partner is stupid because he wouldn’t know where to start. That’s a highly specialised and fundamentally useless skill that I enjoy exercising, but I don’t kid myself that it makes me superior, more useful, or more worthy than someone else whose intelligence is of a different kind. By all means enjoy the things you’re good at — why not? — but beware, I would say, thinking that being good at X means you’re inherently “smarter” than someone who is good at Y. A functioning society needs all kinds of intelligences.