We all know that bitmaps can not be enlarged arbitrarily, because even the most perfect filter can not extract/display sub-pixel information, because it has not been saved (it simply does not exist). The same applies to upscaling. You can create the illusion of sharpness at first glance, but no anti-aliasing technique will allow you to display details that have not been rendered due to the low resolution of the rendered frame. Perhaps it's worth checking whether, in general, using high resolution textures makes sense with DLSS enabled? Maybe smaller textures will not worsen the quality of the image and will boost fps?