Why are character faces blurry in Dota 2 at 4K resolution?

At 4K, DLSS Quality mode made character faces look like they had a soft filter, ruining the detail. I tried switching to Balanced mode, which improved FPS by 8 but made the blurriness worse, a frustrating dead end. Using GamePP DLSS/FSR Image Sampling Calibrator, I increased sharpening intensity to 75 and set render resolution to 100%. RivaTuner showed effective render pixels increased significantly. GamePP quality analysis confirmed the sharpness score improved to 85-92, restoring the crisp texture detail I was missing.