People value intelligence and will apply that label to themselves even if it may not be true. It's a hard thing to measure though IQ does it reasonably well. To those who have a high IQ: what is it like? Can you pick up any book, read it, and understand the gist with minimal repetition? Can you infer solid and accurate conclusions based on a small amount of evidence? Is any subject or discipline up for grabs or do you have to have a keen interest in a particular field in order to flourish? What is something you are able to do that you know is because of your intelligence -- the proverbial 1,000 pound deadlift of the brain, if you will.
There is no point to these questions other than curiosity.
In this case, I think he was referring to the hugely popular on tumblr show called literally Sherlock that was highly praised for its "portrayal" of an intelligent character.
It had a final season so bad people literally memoryholed it, rewrote history to call it always trash, and forget that its the only reason Benedict Cumberbatch got famous, but it was one of the leading examples of "smart is sexy" a decade ago.