The Future is finally here!* (almost)
Deep Learning Super Sampling (DLSS) Ray Reconstruction is making its way into Blender (at least, it's in the works). And the results are, without exaggeration, astonishing.
Unlike "traditional" denoisers, DLSS has a different way of reconstructing an image, and doesn't really care about scene lighting or polygonal complexity. Because of this, it's used in games to "upscale" a rather low-res natively-rendered output to a much higher-res target, like 4K or more. It's very effective and, ironically, despite being an upscaler, nowadays is almost synonymous with the "best quality" rendering preset in games. Simply because more and more devs get lazy and spend less effort on optimization, especially anti-aliasing techniques, simply "offloading" this task to a dedicated (and, unfortunately deeply proprietary) neuralnet upscaler like DLSS.
I bet like me, you have always wondered if this very approach could be used in a traditional 3DCG Creation app like Blender.
Well, wonder no more! Someone took an unfinished alpha version of Blender codebase with a DLSS integration, and compiled it into an actual test build.
Prepare to be amazed.