It really depends but generally speaking just because of the mechanics of it voice-over is easier because there is no hair no makeup no wardrobe no fittings no line memorizing. You don't have to me woken up in Russia at 6 in the morning and go film a scene. It's just easier on the body the family life to do voice-overs.
There is an urgent need for Americans to look deeply into themselves and their actions and musical poetry is perhaps the most effective mirror available. Every newspaper headline is a potential song.
