Supersampling eliminates aliasing.
It doesn't make the game sharp lol
Both the 4k native and supersampled from 8k to 4k are sharp (since there is no blurry AA used in neither).
Are you mistaking the level of aliasing in the image as "level" of sharp?
It eliminates aliasing by "condensing" the image in a lower resolution. It's not your typical anti-aliasing that smoothens the edges, it makes them more defined, ergo sharper.
And no, I'm not mistaking aliasing for sharpening. As I said, refuse to concede and would come up with something to ignore your flawed logic. I sometimes wonder if you're just trolling