Nope! It actually is mathematically how it works. Upscaling does not amplify NOISE, like eg surface boiling, although it does introduce many other artifacts. Noise, specifically, would be smoothed. The problem with upscaling is actually not noise, but oversmoothing, which is why it's paired with sharpening. You can just look at an upsampled signal to see how noise is affected. Boosting gain would increase noise; interpolating samples does not increase noise.
You can test it yourself and see, just go ahead and disable the FSR and frame gen gimmicks entirely while keeping ray tracing on. Hell, disable all AA and motion blur while you're at it, and really take a gander at what actual, unblurred ray tracing looks like.
Edit: also, "with low quality upscaling" lmao I'd love to hear what the implied "high quality upscaling" does differently 😂 something right? It's totally different!!
I'd expect that people will probably look and watch, but that's just because juggling is entertaining