One could say that simplicity is a demonstration of space between thoughts. This makes sense. Complexity, complication, and distraction have little space between thoughts. The space (as in duration) is so brief that cluttered mind or a chasing mind or a repulsing mind is the result. This experience manifests because there also is little space as in empty spaciousness between thoughts/perceptions/labeling/. Inside, one is ricocheting. Simplicity has space.
Simplicity also is experienced as neutral. One is simply present to Presence. Why cultivate simplicity in any way that one can? Because complexity engages the ego while simplicity engages pure Being. With practice, both are then available and integrate each other. Otherwise, all one has to work with is clutter and self-importance, and that’s boring.