A result is the suggestion of spontaneous speech and unadulterated emotion. The irony is that such presentations are highly rehearsed, with each caesura calculated and every syllable stressed in advance.
This is actually a major problem with the entire TV and radio age. People who seem awkward or fake in front of a camera are actually normal people. It is simply not natural to talk directly to a camera lens as if it is a person, it is not natural to speak in a folksy way to a generic audience that you cannot see. People who seem natural in front of a camera, are actually slick, well-practiced professionals. Thus in the modern era, all politicians and most public figures end up being essentially actors.