As far as I can tell, this is nearly everybody's biggest flaw, high IQ or no. I think we just relish the chance to point out a "smart" person's limits more.
Well, there does seem to be a special Silicon Valley version of this where people get incredibly wealthy from their software/web businesses and conclude all they need to do is get into <some other radically-different field> and they'll get that "figured out" just as easily. It's a unique kind of hubris that doesn't usually pan out.
If you are the best pro basketball player of all time then you should also be at least among the best pro baseball players too.