There are some projects that swap out textures for higher res versions. But I think the bigger advantage is for distant objects - if you zoom in the goldeneye

There are some projects that swap out textures for higher res versions. But I think the bigger advantage is for distant objects - if you zoom in the goldeneye screenshot, you can see the face texture of the guy at the other end of the hall. If the regular native resolution had been used and upscaled afterwards, you wouldn't see the face at all, just a face-coloured blur