It's almost the same discussion as regarding omnidirectional and dipole speakers. In the right acoustical environment they can sound spectacular. But they, like beaming and reflecting soundbars, are room dependent. You are more in control of circumstances when you can free yourself from the oftentimes unpredictable nature of room acoustics.
If you are a sound designer, and a good interior decorator, I suppose you can make anything work. But I still think that soundbars with rear speakers are a real advance.