Yes, please file a bug. If you are able to provide example project that demonstrates the issue and a few screenshots of desired vs current look, it would be super helpful.
In general, there are some limits to how ray tracing works with subsurface scattering. Shadow maps are currently required for certain effects (such as transmission) to work correctly. This is because ray traced shadows work by starting a ray at the receiving surface and tracing it toward the light. Shadow maps do the opposite: start from light and “trace” towards scene. Shadow maps therefore allow us to approximate object thickness.
My gut feeling is that a shadow map will be required to achieve the subsurface look you are after (i.e. shadow maps would still need to be rendered even when RT shadows are on, but only used for SSS). Perhaps a specialized path can be also implemented using ray tracing, but no work has been done on this specifically so far.