So are Springsteen's songs. They sound like an interior monologue. We may be growing distrustful of all public rhetoric. There is something about the wiring in our heads that makes any collection of two seem wrong and incomplete. And if you go for four, you'll risk being shut out of people's listening space.
Sounds evoke a visceral feeling.
The Italian language, for example, is full of vowels, which means that you speak it at the front of the mouth. When we listen to Italian words, we repeat them in our mind's ears. They make us feel warm, hugged, and innocent. All language has a subtle music of meaning. Using words that contain lots of consonants suggests that you really mean business.