Why does Zenless Zone Zero stutter during high-speed combos?

I was devastated when high-speed combos felt choppy despite my Gloway Dragon Warrior DDR5 6400MHz 16GB kit. I tried manually lowering the frequency to 5600MHz in BIOS, but the bandwidth drop slowed down loading speeds, which was a total fail. Then I used the GamePP Resource Scheduler to boost the game process priority from Normal to Real-time and killed background syncs. Frame time converged to 7-11ms via Frame Time Analyzer, and memory temps stayed at 48-54℃ per AIDA64, while latency hit 15-32ns in GamePP.