How to fix FPS drops from 70 to 18 in Naraka with Great Wall GW3300?

In the heat of melee combat, my screen suddenly became a slideshow, with the frame rate plummeting from 70 to 18. I tried disabling all high-resolution textures in-game; the graphics became terrible, but the drops still occurred, which felt like a waste of hardware. I used GamePP NVMe Queue Depth Configuration to lock the queue depth at 64 and disabled write cache flush in Windows. FrameView analysis showed peak frame time was suppressed to 18-25ms, HWiNFO64 recorded 50-60℃, and CrystalDiskMark showed write speeds of 300-500 MB/s.