The link shows path tracing running in real time with a more advanced SGVF filter than what NVIDIA presented a couple years ago (used in PICA PICA). I think it's more than enough.Rather than linking me to a sprawling site of papers (and in particular the link takes me to denoising), how about you link to the specific paper or reference that shows how ray sampling can be homogenised across different requirements? I'm not saying you're wrong, but there's no way I'm going to spend however many hours searching through that site to find research that shows yes, you can reuse data and samples for relfections and lighting.
Firstly, how big is that audience? How many millions of gamers will devs have to target their raytracing R&D towards? Secondly, you haven't answered the question about what do gamers actually use? It's not a monolithic group. There are lots of gamers. Do they choose higher quality settings at lower framerates on average, or lower quality settings to get higher framerates?
PC gamers are used nowadays to high framerates/resolutions because the choice for high fidelity simply doesn't exist. All they have is console ports. Without data it's impossible to answer your question. Then again, if RT makes its way to consoles then the answer would be: many millions of gamers