The Eevee SSGI thread clearly shows there is a lot of demand for the feature, and examples do show that it is able to bring good results where the current GI is insufficient.
Now if Eevee was capable of generating SSGI from virtual camera angles and stitching the result into the rendered view (an imaginary 360 degree camera for instance), or being able to utilize any kind of volume probe illumination as an assistive tool, then things could become interesting. I do not know if such a thing would have to wait for Vulkan first.