I'd be careful with both of those generalizations.

PhD's aren't necessarily smarter than anyone else. On average, PhD's -- especially at top institutions -- probably typically have above average IQs. But I'd wager a guess that the same is true for non-PhD's working for top employers (or starting successful companies).

Similarly, while it's true that PhD's have very deep knowledge about a very narrow topic, that doesn't preclude them from also having a lot of knowledge about many other topics. Especially since intellectual curiosity probably correlates better with PhD than raw intelligence.