"
"kasparov has barely any to show"
Say what? Kasparov created absolutely beautiful art - fantastic conceptions that changed the way we think about chess. Would you also say that Mozart, Shakespeare, Michelangelo achieved nothing in their careers? "
Quite simply I count chess as a game not as an art. The three people you named have all done absolutely brilliant work and achieved far more than most people. However when I get asked who achieved more einstein or kasparov, Einstein is the only one I can name here. I would also not compare the achievments of the great footballer or poker player or any person who is amazing in any game to the ones of Einstein, mainly because it just doesn't affect nearly enough people.
There is also a misconception that Cognitive speed relates to having a high IQ. Timed tests falsly omit the kind of intelligence that can solve very deep complex situations that some would not achieve whatever the time allowed. Einstein was said not to be quick and was only an above average acedemic, yet he was able to view the world like no other. Deep slow chess players can solve anything but can suck at blitz.