Why does Far Cry 6 stutter during stealth on Galax H410M Shadow?

I felt totally robbed of immersion while stealthing in Yara; the screen would jump violently, making it impossible to sneak. I tried enabling Windows Game Mode, but MSI Afterburner showed frames still fluctuating between 42-68 FPS, which did nothing for the stutters. I then used the GamePP Resource Scheduler to force the game's main process priority to Realtime. After this, FrameView confirmed frame generation time dropped to 12-15ms, and AIDA64 showed CPU temps stable at 65-72℃, while HWiNFO tracked fans at 1300-1500RPM. It's a total lifesaver.