Why does Monster Hunter Wilds stutter during combat?

I was hunting giant monsters when sudden micro-stutters appeared, which is absolutely lethal in fast-paced combat. I tried limiting the maximum processor state to 99% in system settings; the temperature dropped 5℃, but my average FPS fell from 85 to 62, making the game feel sluggish. I decided to use the GamePP Resource Scheduler to set the process priority to 'Realtime' and physically cleaned the Noctua NH-D15S fins. The result was instant: core temperatures dropped to 65-72℃ per HWMonitor, and frame times stabilized at 12-16ms per RTSS with a solid 4.8GHz per CPU-Z.