Actually RTX performance in ray-tracing very good. With each ray intersection is handled by not-so-simple shader program and given DXR effects are mostly added on top of existing effects which already stress shaders a lot (or replace much cheaper shader based effects) it is no wonder performance with DXR enabled is worse than with it disabled. This will never change! Some of these shaders which are executed with each ray intersection could be made into fixed hardware and with this approach performance would be much better but that would allow far less flexibity and would require even more silicon. DXR is designed to be fully programmable so any effect can be done with it from simple reflections to more elaborate path-tracing implementations and even things which one could hardly call ray-tracing like using RT cores to calculate realistic sound effects, etc. Of course I would not expect first HW implementation to be most optimal and some tweaks can surely be made to make RT better. More optimizations can be however expected from game developers than from Nvidia or anyone else.