I bring it up because, to me, the system reqs basically translate to, "If you're using settings close to these then you need hardware close to this.". Put differently, they're not very useful outside of a generic ballpark.
Well, there are so many different elements to graphical settings that a "generic ballpark" is about all you can possibly get. Or a super long list that lists every permutation of the settings. All of the settings from different anti-aliasing, ambient occlusions etc, to ray-tracing (which I guess has multiple settings as well) to resolution to frame rate, all of this contributes to how well your rig can handle it.
It is not possible to get accurate estimations since it all ALSO depends on the actual game and the scene you are looking at. A wide-area shot over the city vs a narrow corridor scene also put different stress on the system.
I read somewhere that RT is better in the shadows department, builds them better.
For me, so far, the images with RT have too much of a mirror effect to them.
Well, duh. Shadows and reflections are ALL that ray-tracing affects. Nothing else. It literally tracks the path of rays of light the way they would behave in real world. Contrary to how this used to be done in graphic cards, via various forms of trickery and faking it.
I am curious without RT on what DLSS can do. If you can do ultra settings will DLSS improve it somehow, or it is useless?
From what I have learned, DLSS can provide a huge buff to framerate in the HIGH stress situations, but ONLY in those situations. When the card is working its ass out and framerate would normally be low, DLSS improves it a lot. Outside of that there isn't much difference to normal methods, so far at least. DLSS is very new tech, to keep in mind. Also DLSS is exclusive to Nvidia currently.