If RT becomes a thing, NVIDIA will just add more tensor cores. Currently 8 per SM of 64 cores, they can make it 1:1 64 shader cores and 64 tensor, and we have a 4K144 raytrace monster.
Why would they add more tensors cores when they have little to do with ray tracing itself. They need to add more RT cores, if they want more GigaRays.