As someone who has always done well in an academic setting, I am sympathetic with people who stress that knowledge does not equate smartness.
Of course, having knowledge is no guarantee that a person has the logic and reasoning skills that are required for a person to be considered smart.
Being smart is so much more than simply knowing facts!
My problem was actually the opposite. Because I performed well academically, people would assume I also knew a lot of facts. And the truth is, especially during my late teens, my brain had little time for trivia. My brain was more interested in understanding 'hows' and 'whys'.
Whilst it is true I had a fair bit of general knowledge from all the books I read, my ability to regurgitate trivia facts was something I had to work on.
The point I am getting to is: does that make knowledge worthless?
I don't believe it does.
And not simply because it is just so satisfying to win money in front of people on a pub quiz machine!
A good general knowledge enriches and enhances a person's understanding and appreciation of the world around them, in my opinion.
And whilst a good general knowledge may not GUARANTEE that someone is smart, it certainly indicates qualities found in very smart people: a keen interest in the world, avid reader, etc.