intelligence is correlated with (and arguably defined by) insight, so that's a reasonable, if fallible, belief.

intelligence doesn't guarantee insights in areas outside expertise, but it's certainly more promising in that regard.

what's baffling are the high expectations in the populace for the general opinions of famous but not demonstrably intelligent people, e.g., many actors, tv personalities, singers, etc. (comedians are a notable exception, as insight is integral to their craft).