How do I stop CPU throttling in Dying Light 2 with a Noctua NH-D9L?

I was mid-boss when the frame rate crashed from 60 to 45 FPS. My CPU hit 85-90°C per HWiNFO, causing total stutter. I tried locking the fan to 100%, but it was deafening and only dropped temps by 3°C. That was a dead end. I opened GamePP Fan Curve Configurator and set the curve to 80% RPM at 75°C. Now, AIDA64 shows temps stable at 72-75°C. Frame time is consistent at 16.1-17.2ms via RTSS. It's quiet and smooth.