Their point splatting method is orthogonal to level-of-detail rendering (they reference a few papers which try to do this), so both point splatting and LoD could be combined in the future for an even greater performance gain during rendering. They already implement occlusion and frustum culling.

Point splatting does introduce a lot of noise though, and their denoiser introduces ghosting, but they say a more sophisticated denoiser would give considerably better quality.