While this works OK-ish for static images, it is almost unusable for animations. But for static images, blur+sharpen in Photoshop has worked OK-ish, too, for many years.

So the practical benefit of this is negligible.

What we need is a denoising technique where the denoising artifacts move convincingly with the features of the scene, so that you can use it for movies and games.

Oh and for games, as long as this is NVIDIA-exclusive, developers have to treat it as an optional add-on. For multiplayer games, that implies that Ray Tracing may never show details (such as a reflection of an enemy) that would give a strategical advantage.

Plus the real issue with contemporary game development is that consoles make a majority of the revenue (due to less piracy) but they choke when you have 50k+ polygons on an animated character. And you'll be limited to 2 GB GPU RAM on 30% of your PC player base, because they use laptop GPUs.

In the end, then, you usually don't have enough detail to make ray-tracing look good. It looks amazing for high-poly curved surfaces, such as those used for offline-rendered cinema movies. But on a blocky realtime game model, ray-tracing may also highlight artifacts.

Here's a ray-traced low poly bunny: https://i.imgur.com/MGotRC7.png

Notice how clearly you can see that it is low poly. In a rasterization engine, one would "fix" this by blurring the edges with shaders and bending the corners with normal maps.

So in a sense, ray-tracing is too honest to work well with current video game models.