Why does a 16GB GPU still stutter in Kingdom Come 4K?

I can't stand it—a card with 16GB of VRAM still has instant stutters in medieval towns; it's ridiculous for 2026. I first tried 'Extreme Performance' mode in the driver; it gained 10 FPS but caused severe screen tearing, which was a joke of a solution. I used the GamePP DLSS/FSR Image Sampling Calibrator to lock the sampling rate at 90% and optimized sharpening. Frame times stabilized at 11-16ms per FrameView, and GPU power consumption remained at 180-210W per HWiNFO. Now it's finally stable.