I believe the word "intelligence" should pay a compliment to those people who life pays compliment to, in terms of their ability to find solutions to real world problems, and carry out their execution. If we can't do that (and I'm not saying we can), then measuring some idea of "intelligence" and assigning a flat score to it is counterproductive.
How quickly one picks up on board games... I don't know. Maybe it matters. Maybe it means something. What if those who pick up on board games slower are building a much deeper model in their mind and can reach deeper insights than their opponents? Would speed then be a misleading indicator?
Take me, I pick up on new things slower than many might. But over time I get a much better idea about it and become frustrated with the superficial way my peers see it. Am I stupid, am I smart? Who knows. Sometimes gaining too much insight is actually harming performance for real world problems. Sometimes it helps. I'm neither ashamed nor proud by this arrangement. I just have my dials set this way.
Is life like a big logical puzzle? Shouldn't we judge people by their life performance if it is? Should we not judge people by simple puzzle games if it isn't?
Lots of questions, and if you dig deeper, you'll find the experts don't know much better than us after all.
The way we measure intelligence is much like we measure candidate performance during job interviews. It's full of "experts" with recommendations, and yet the questions and challenges have little to do with the actual job, or the job performance of the candidate when hired.