From an evolutionary perspective, the narrow focus lends itself to successful hunting, problem solving, and survival outside a tribe. Civilization has a limited but growing need for such loners because they can solve deep focus problems that high social IQ types cannot.
Big gov lovers are proportional to population density, not IQ. Many high IQ types get indoctrinated into leftism simply because universities and brainy employment tends to be in high population density cities rather than the hinterlands.
Not to criticize here, but something I find paradoxical to my own assumptions: problem solving is considered a creative, hence broadly focused tendency. Hunting, I would think, requires an awareness of environment and constant scanning, and a narrow focus would be an impediment.
This is 60's and 70's thinking, and views on this may have changed. Again, these are just musings.